Skip a GC test known to be flaky:

  https://issues.guix.gnu.org/issue/37425
  https://github.com/golang/go/issues/27636

--- go/src/runtime/gc_test.go	2019-09-16 23:10:18.200680387 +0200
+++ go/src/runtime/gc_test.go	2019-09-16 23:11:50.324360646 +0200
@@ -27,6 +27,9 @@ func TestGcSys(t *testing.T) {
 	if runtime.GOOS == "linux" && runtime.GOARCH == "arm64" {
 		t.Skip("skipping test; GOOS=linux GOARCH=arm64 https://github.com/golang/go/issues/27636")
 	}
+	if runtime.GOOS == "linux" {
+		t.Skip("skipping test; GOOS=linux https://issues.guix.gnu.org/issue/37425")
+	}
 	got := runTestProg(t, "testprog", "GCSys")
 	want := "OK\n"
 	if got != want {
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<tr><td><span title='2023-09-10 02:00:00 +0200'>2023-09-10</span></td><td><a href='/guix/commit/gnu/packages/ftp.scm?id=4c4ff2e1f077786d85c47ceeec10340a864e17f1'>gnu: vsftpd: Fix build with recent OpenSSL.</a><span class='msg-avail'>...</span></td><td>Tobias Geerinckx-Rice</td></tr>
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