gitweb: Disable gpg signing in tests

In case the local git config has gpg signing enabled for commits, it
causes the test commit to fail. Ensure gpg signing is disabled to
avoid this failure.

Tests:

- Gitweb functional tests passed. (Randomly there is a failure, but
  seems unrelated, see #2349.)

Signed-off-by: James Valleroy <jvalleroy@mailbox.org>
Reviewed-by: Veiko Aasa <veiko17@disroot.org>

plinth/modules/gitweb/tests/test_functional.py

@@ -121,7 +121,7 @@ def _create_local_repo(path):
     create_repo_commands = [
         'git init -q', 'git config http.sslVerify false',
         'git -c "user.name=Tester" -c "user.email=tester" '
-        'commit -q --allow-empty -m "test"'
+        'commit -q --allow-empty --no-gpg-sign -m "test"'
     ]
     for command in create_repo_commands:
         subprocess.check_call(command, shell=True, cwd=path)
@@ -155,7 +155,8 @@ def _create_branch(repo, branch):
                                [
                                    'git', '-c', 'user.name=Tester', '-c',
                                    'user.email=tester', 'commit', '-q',
-                                   '--allow-empty', '-m', 'test_branch1'
+                                   '--allow-empty', '--no-gpg-sign', '-m',
+                                   'test_branch1'
                                ],
                                ['git', 'push', '-q', '-f', repo_url, branch]]
         for command in add_branch_commands: