fetchGit: add simple test for ssh fetching

Also move tests to separate files which are auto-imported. This should allow people adding tests concurrently without introducing merge conflicts

tests/nixos/fetch-git/testsupport/setup.nix

@@ -78,19 +78,27 @@ in
           self.name = name
           self.path = "/tmp/repos/" + name
           self.remote = "http://gitea:3000/test/" + name
+          self.remote_ssh = "ssh://gitea/root/" + name
           self.git = f"git -C {self.path}"
           self.create()
 
         def create(self):
+          # create ssh remote repo
+          gitea.succeed(f"""
+            git init --bare -b main /root/{self.name}
+          """)
+          # create http remote repo
           gitea.succeed(f"""
             curl --fail -X POST http://{gitea_admin}:{gitea_admin_password}@gitea:3000/api/v1/user/repos \
               -H 'Accept: application/json' -H 'Content-Type: application/json' \
               -d {shlex.quote( f'{{"name":"{self.name}", "default_branch": "main"}}' )}
           """)
+          # setup git remotes on client
           client.succeed(f"""
             mkdir -p {self.path} \
             && git init -b main {self.path} \
-            && {self.git} remote add origin {self.remote}
+            && {self.git} remote add origin {self.remote} \
+            && {self.git} remote add origin-ssh root@gitea:{self.name}
           """)
     '';
     testScript = ''