github actions: Fix up validate-kernel-commits-comment.yml

There was some conditional formatting for the checkout that really isn't
necessary since we're preforming this with-in ctrliq/kernel-src-tree.
This came about because its hard to test the on_complete trigger and
using a dispatch does work, so lets just use the same as dispatch
method.

Author: PlaidCat

.github/workflows/validate-kernel-commits-comment.yml

@@ -213,7 +213,7 @@ jobs:
 
       - name: Checkout PR head for JIRA check
         env:
-          CLONE_URL: ${{ github.event_name == 'workflow_dispatch' && format('{0}/{1}.git', github.server_url, github.repository) || github.event.workflow_run.repository.clone_url }}
+          CLONE_URL: ${{ format('{0}/{1}.git', github.server_url, github.repository) }}
           BASE_REF: ${{ steps.pr_metadata.outputs.base_ref }}
           HEAD_SHA: ${{ steps.pr_metadata.outputs.head_sha }}
         run: |