Fix case when new release commit pushed but still master used for sync (

#8112)

.github/workflows/sync-supported-chains.yml

@@ -35,6 +35,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           path: nethermind
+          ref: ${{ github.event.workflow_run.head_branch || github.ref_name || 'master' }}
       - name: Set Matrix
         id: set-matrix
         run: |
@@ -100,6 +101,7 @@ jobs:
         uses: actions/checkout@v4
         with:
           clean: true
+          ref: ${{ github.event.workflow_run.head_branch || github.ref_name || 'master' }}
 
       - name: Checkout tests repository
         uses: actions/checkout@v4
@@ -365,5 +367,5 @@ jobs:
           ref: "main"
           token: "${{ steps.gh-app.outputs.token }}"
           inputs: '{
-            "nethermind_branch": "${{ github.ref}}"
+            "nethermind_branch": "${{ github.event.workflow_run.head_branch }}"
           }'