github: return pull request in updated-asc order by ListPRs

Return the pull request by ListPRs in ascending updated order.
This has the effect that on directorius startup the PR that has been
updated the longest time ago will become #1 instead of a random PR.

internal/githubclt/listprs.go

@@ -65,7 +65,7 @@ type listPRsQuery struct {
 				}
 			} `graphql:"... on PullRequest"`
 		}
-	} `graphql:"search(query: $query, type: ISSUE, first: 100, after: $pullRequestCursor)"`
+	} `graphql:"search(query:$query, type:ISSUE, first:100, after:$pullRequestCursor)"`
 }
 
 // ListPRs returns an iterator over all open pull requests of the repository.
@@ -74,7 +74,7 @@ type listPRsQuery struct {
 func (clt *Client) ListPRs(ctx context.Context, owner, repo string) iter.Seq2[*PR, error] {
 	vars := map[string]any{
 		"pullRequestCursor": (*githubv4.String)(nil),
-		"query":             githubv4.String(fmt.Sprintf("repo:%s/%s is:pr is:open", owner, repo)),
+		"query":             githubv4.String(fmt.Sprintf("repo:%s/%s is:pr is:open sort:updated-asc", owner, repo)),
 	}
 
 	var prs []*PR