fix(githubPrAction): properly construct repoUrl

Signed-off-by: Phil Kuang <pkuang@factset.com>

.changeset/smart-items-fry.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+Fix broken GitHub PR action due to malformed `repoUrl`

plugins/scaffolder-backend/src/scaffolder/actions/builtin/publish/githubPullRequest.ts

@@ -72,7 +72,7 @@ export const defaultClientFactory = async ({
   const octokitOptions = await getOctokitOptions({
     integrations,
     credentialsProvider: githubCredentialsProvider,
-    repoUrl: `https://${encodedHost}/${encodedOwner}/${encodedRepo}`,
+    repoUrl: `${encodedHost}?owner=${encodedOwner}&repo=${encodedRepo}`,
     token: providedToken,
   });