fix(gitlab): use project path wherever possible

Turns out that all we need is the path, and not the project id. The path
is way more user friendly, and we can easily get it from a CI variable
or combine it from the namespace & project name.

cmd/rp/cmd/run.go

@@ -62,8 +62,7 @@ func run(cmd *cobra.Command, _ []string) error {
 		logger.DebugContext(ctx, "using forge GitLab")
 		f, err = gitlab.New(logger, &gitlab.Options{
 			Options: forgeOptions,
-			Path:    flagOwner,
-			Repo:    flagRepo,
+			Path:    fmt.Sprintf("%s/%s", flagOwner, flagRepo),
 		})
 		if err != nil {
 			logger.ErrorContext(ctx, "failed to create client", "err", err)