feat(3p/gerrit_plugins): init Gerrit checks plugin

The Gerrit Checks plugin adds a new tab to the Gerrit UI, which is
intended for display of status of automated checks which are being run.
We can use this for e.g. reporting the run status of our CI builds/other
stuff.

Change-Id: Ib0d9a8ae68061a76191a56d467d915100b766e1b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1462
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>
Reviewed-by: glittershark <grfn@gws.fyi>

ci-builds.nix

@@ -70,6 +70,7 @@ in lib.fix (self: {
 
   gerrit = with depot.third_party.gerrit_plugins; [
     depot.third_party.gerrit
+    checks
     owners
   ];
 

third_party/gerrit_plugins/default.nix

@@ -22,4 +22,17 @@ in
       cp -R "${src}/owners-common" "$out/owners-common"
     '';
   };
+
+  # https://gerrit.googlesource.com/plugins/checks
+  checks = buildGerritBazelPlugin {
+    name = "checks";
+    depsOutputHash = "1nk63ahlynqn5my7lzy7vsax07n585ndmvbnz2xbwkppl1m7j56l";
+    src = pkgs.fetchgit {
+      url = "https://gerrit.googlesource.com/plugins/checks";
+      rev = "36d9e5c61b95ade98883ded5eb1e168c28ef99bf";
+      sha256 = "03abn4m9x8cinx86c41hrazg0kgwvjfak3w155sca1ikq4605pma";
+      deepClone = true;
+      leaveDotGit = true;
+    };
+  };
 }