Use shared gtest instead of submodule

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 617e4b2..2857875 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,7 +18,6 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
 include(GNUInstallDirs)
 
 project(leelaz)
-add_subdirectory(gtest EXCLUDE_FROM_ALL) # We don't want to install gtest, exclude it from `all`
 
 # Required Packages
 set(Boost_MIN_VERSION "1.58.0")
@@ -27,6 +26,7 @@ find_package(Boost 1.58.0 REQUIRED program_options filesystem)
 find_package(Threads REQUIRED)
 find_package(ZLIB REQUIRED)
 find_package(OpenCL REQUIRED)
+find_package(GTest REQUIRED)
 # We need OpenBLAS for now, because we make some specific
 # calls. Ideally we'd use OpenBLAS is possible and fall back to
 # not doing those calls if it's not present.
@@ -93,6 +93,7 @@ include_directories(${IncludePath})
 include_directories(${Boost_INCLUDE_DIRS})
 include_directories(${OpenCL_INCLUDE_DIRS})
 include_directories(${ZLIB_INCLUDE_DIRS})
+include_directories(${GTEST_INCLUDE_DIRS})
 
 if((UNIX AND NOT APPLE) OR WIN32)
     include_directories(${BLAS_INCLUDE_DIRS})
@@ -141,7 +142,8 @@ target_link_libraries(tests ${Boost_LIBRARIES})
 target_link_libraries(tests ${BLAS_LIBRARIES})
 target_link_libraries(tests ${OpenCL_LIBRARIES})
 target_link_libraries(tests ${ZLIB_LIBRARIES})
-target_link_libraries(tests gtest_main ${CMAKE_THREAD_LIBS_INIT})
+target_link_libraries(tests ${GTEST_BOTH_LIBRARIES})
+target_link_libraries(tests ${CMAKE_THREAD_LIBS_INIT})
 
 include(GetGitRevisionDescription)
 git_describe(VERSION --tags)
-daemon.sh'>
<input type='hidden' name='id' value='02c9a0697632847e9ad83f6ba42b12eef29bb0df'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=02c9a0697632847e9ad83f6ba42b12eef29bb0df'>root</a>/<a href='/guix/log/tests?id=02c9a0697632847e9ad83f6ba42b12eef29bb0df'>tests</a>/<a href='/guix/log/tests/guix-daemon.sh?id=02c9a0697632847e9ad83f6ba42b12eef29bb0df'>guix-daemon.sh</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/tests/guix-daemon.sh?id=02c9a0697632847e9ad83f6ba42b12eef29bb0df&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-09-28 21:06:36 -0500'>2020-09-28</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=d8934360d2453a403b5433e71d09188e4ed23b57'>tests: Simplify shell exit status negation;</a><span class='msg-avail'>...<span class='msg-tooltip'>* tests/guix-archive.sh, tests/guix-build-branch.sh, tests/guix-build.sh,
tests/guix-daemon.sh, tests/guix-download.sh, tests/guix-environment.sh,
tests/guix-gc.sh, tests/guix-git-authenticate.sh, tests/guix-graph.sh,
tests/guix-hash.sh, tests/guix-lint.sh, tests/guix-pack-relocatable.sh,
tests/guix-pack.sh, tests/guix-package-aliases.sh, tests/guix-package-net.sh,
tests/guix-package.sh: Use the shell '!' keyword to negate command exit status
in place of 'if ...; then false; else true; fi'
</span></span></td><td>Eric Bavier</td></tr>
<tr><td><span title='2019-10-16 22:53:40 +0200'>2019-10-16</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=81c580c8664bfeeb767e2c47ea343004e88223c7'>daemon: Make 'profiles/per-user' non-world-writable.</a><span class='msg-avail'>...<span class='msg-tooltip'>Fixes &lt;https://bugs.gnu.org/37744&gt;.
Reported at &lt;https://www.openwall.com/lists/oss-security/2019/10/09/4&gt;.

Based on Nix commit 5a303093dcae1e5ce9212616ef18f2ca51020b0d
by Eelco Dolstra &lt;edolstra@gmail.com&gt;.

* nix/libstore/local-store.cc (LocalStore::LocalStore): Set 'perUserDir'
to #o755 instead of #o1777.
(LocalStore::createUser): New function.
* nix/libstore/local-store.hh (LocalStore): Add it.
* nix/libstore/store-api.hh (StoreAPI): Add it.
* nix/nix-daemon/nix-daemon.cc (performOp): In 'wopSetOptions', add
condition to handle "user-name" property and honor it.
(processConnection): Add 'userId' parameter.  Call 'store-&gt;createUser'
when userId is not -1.
* guix/profiles.scm (ensure-profile-directory): Note that this is now
handled by the daemon.
* guix/store.scm (current-user-name): New procedure.
(set-build-options): Add #:user-name parameter and pass it to the daemon.
* tests/guix-daemon.sh: Test the creation of 'profiles/per-user' when
listening on a TCP socket.
* tests/store.scm ("profiles/per-user exists and is not writable")
("profiles/per-user/$USER exists"): New tests.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-27 23:33:48 +0200'>2019-06-27</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=5cc1075a76392666d3d733837f5c6252b1e48002'>Merge branch 'master' into core-updates</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-27 11:14:42 +0200'>2019-06-27</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=c30d117822a8ca26cd8c06c0a3974955bef68eac'>tests: Avoid TCP port collision between lint.scm and guix-daemon.sh.</a><span class='msg-avail'>...<span class='msg-tooltip'>This could lead to random deadlocks in one of these two tests when
running "make check -j5".

* tests/guix-daemon.sh (tcp_socket): Change port to 9998 to avoid
collision with tests/lint.scm.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-14 21:57:39 +0200'>2019-06-14</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=1ba0b1e6ec41afd94a3c5f907b1122204dcb5d9d'>packages: Remove 'search-bootstrap-binary'.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/packages.scm (%bootstrap-binaries-path, search-bootstrap-binary):
Remove.
* gnu/packages/bootstrap.scm (bootstrap-executable): Export.
* guix/tests.scm (bootstrap-binary-file, search-bootstrap-binary):
Export.
* tests/derivations.scm: Remove (gnu packages) import.
* tests/grafts.scm: Likewise.
* tests/guix-daemon.sh: Likewise.
</span></span></td><td>Ludovic Courtès</td></tr>