ci: refine PR search query to avoid querying whole github (#1330)

* ci: refine PR search query to improve label handling in GitHub Action workflow

- Replaced `label` with `search_query` for better flexibility.
- Added support for multiple labels (`PR_LABEL` and `${PR_LABEL}-c3`).

* ci: fix PR search query for proper label matching in workflow

- Adjusted `label` query syntax to correctly handle multiple labels.

* Update .github/workflows/sunnypilot-master-dev-prep.yaml

.github/workflows/sunnypilot-master-dev-prep.yaml

@@ -118,8 +118,8 @@ jobs:
         run: |
           # Use GitHub API to get PRs with specific label, ordered by creation date
           PR_LIST=$(gh api graphql -f query='
-            query($label:String!) {
-              search(query: $label, type:ISSUE, first:100) {
+            query($search_query:String!) {
+              search(query: $search_query, type:ISSUE, first:100) {
                 nodes {
                   ... on PullRequest {
                     number
@@ -149,7 +149,7 @@ jobs:
                   }
                 }
               }
-            }' -F label="is:pr is:open label:${PR_LABEL} draft:false sort:created-asc")
+            }' -F search_query="repo:${{ github.repository }} is:pr is:open label:${PR_LABEL},${PR_LABEL}-c3 draft:false sort:created-asc")
 
           PR_LIST=${PR_LIST//\'/}
           echo "PR_LIST=${PR_LIST}" >> $GITHUB_OUTPUT