Fix building against Lens 5 by commenting out type signatures(!).

Taken from upstream:

  https://github.com/ganeti/ganeti/commit/5e30bad1bba63c9f6c782003ef2560f107a0ba24

diff --git a/src/Ganeti/Network.hs b/src/Ganeti/Network.hs
index 1cb6aa1ec..696c1cd1b 100644
--- a/src/Ganeti/Network.hs
+++ b/src/Ganeti/Network.hs
@@ -87,11 +87,11 @@ data PoolPart = PoolInstances | PoolExt
 addressPoolIso :: Iso' AddressPool BA.BitArray
 addressPoolIso = iso apReservations AddressPool
 
-poolLens :: PoolPart -> Lens' Network (Maybe AddressPool)
+--poolLens :: PoolPart -> Lens' Network (Maybe AddressPool)
 poolLens PoolInstances = networkReservationsL
 poolLens PoolExt = networkExtReservationsL
 
-poolArrayLens :: PoolPart -> Lens' Network (Maybe BA.BitArray)
+--poolArrayLens :: PoolPart -> Lens' Network (Maybe BA.BitArray)
 poolArrayLens part = poolLens part . mapping addressPoolIso
 
 netIpv4NumHosts :: Network -> Integer
diff --git a/src/Ganeti/Utils/MultiMap.hs b/src/Ganeti/Utils/MultiMap.hs
index d54da3ab0..279e9335a 100644
--- a/src/Ganeti/Utils/MultiMap.hs
+++ b/src/Ganeti/Utils/MultiMap.hs
@@ -91,7 +91,7 @@ multiMap :: (Ord k, Ord v) => M.Map k (S.Set v) -> MultiMap k v
 multiMap = MultiMap . M.filter (not . S.null)
 
 -- | A 'Lens' that allows to access a set under a given key in a multi-map.
-multiMapL :: (Ord k, Ord v) => k -> Lens' (MultiMap k v) (S.Set v)
+--multiMapL :: (Ord k, Ord v) => k -> Lens' (MultiMap k v) (S.Set v)
 multiMapL k f = fmap MultiMap
                  . at k (fmap (mfilter (not . S.null) . Just)
                          . f . fromMaybe S.empty)
-- 
2.41.0

/system/accounts.scm'>
<input type='hidden' name='id' value='053accdde356eaf84751b16d3aaf1425f410a70b'/><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=053accdde356eaf84751b16d3aaf1425f410a70b'>root</a>/<a href='/guix/log/gnu?id=053accdde356eaf84751b16d3aaf1425f410a70b'>gnu</a>/<a href='/guix/log/gnu/system?id=053accdde356eaf84751b16d3aaf1425f410a70b'>system</a>/<a href='/guix/log/gnu/system/accounts.scm?id=053accdde356eaf84751b16d3aaf1425f410a70b'>accounts.scm</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/gnu/system/accounts.scm?id=053accdde356eaf84751b16d3aaf1425f410a70b&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2023-10-05 23:14:54 +0200'>2023-10-05</span></td><td><a href='/guix/commit/gnu/system/accounts.scm?id=97927608cb4f9c5d721115f1cb638de17ac38e62'>Revert "system: accounts: Export &lt;user-account&gt;."</a><span class='msg-avail'>...<span class='msg-tooltip'>This reverts commit 03795e2ba27424fc98957da00f6c71325e7ae425.
Fixes &lt;https://issues.guix.gnu.org/66279&gt;.
</span></span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2023-08-20 02:00:00 +0200'>2023-08-20</span></td><td><a href='/guix/commit/gnu/system/accounts.scm?id=5a2c3352d8f8a08a5ba01542a3f282799e503d33'>Revert "gnu: system: Add home-directory-permissions field to &lt;user-account&gt;."</a><span class='msg-avail'>...<span class='msg-tooltip'>This reverts commit e9a5eebc785cb843034b38c5c5a6dd10904bdf2a, which
as far as I can tell breaks system roll-backs thusly:

[...]
In gnu/build/accounts.scm:
   239:27  3 (_ #&lt;&lt;password-entry&gt; name: "root" password: "x" uid: 0 gid: 0 real-name: "System &gt;)
In unknown file:
           2 (string-join ("root" "x" "0" "0" "System administrator" "/root" #t) ":" #&lt;undefined&gt;)
In ice-9/boot-9.scm:
  1685:16  1 (raise-exception _ #:continuable? _)
  1685:16  0 (raise-exception _ #:continuable? _)

ice-9/boot-9.scm:1685:16: In procedure raise-exception:
In procedure string-append: Wrong type (expecting string): #t
</span></span></td><td>Tobias Geerinckx-Rice</td></tr>
<tr><td><span title='2023-08-25 15:12:54 +0200'>2023-08-25</span></td><td><a href='/guix/commit/gnu/system/accounts.scm?id=e9a5eebc785cb843034b38c5c5a6dd10904bdf2a'>gnu: system: Add home-directory-permissions field to &lt;user-account&gt;.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/system/accounts.scm (&lt;user-account&gt;)[home-directory-permissions]: New
field.
(user-account-home-directory-permissions): New accessor.
* gnu/build/activation.scm (activate-users+groups): Use home directory
permission bits from the user account object.
* doc/guix.texi (User Accounts): Document new field.

Signed-off-by: Josselin Poiret &lt;dev@jpoiret.xyz&gt;
</span></span></td><td>David Thompson</td></tr>
<tr><td><span title='2023-07-26 10:40:16 -0400'>2023-07-26</span></td><td><a href='/guix/commit/gnu/system/accounts.scm?id=03795e2ba27424fc98957da00f6c71325e7ae425'>system: accounts: Export &lt;user-account&gt;.</a></td><td>Maxim Cournoyer</td></tr>