Revert "Fix problem with fetch depth of 0"

This reverts commit 49f82a1.

Author: AB-xdev

.github/workflows/update-from-template.yml

@@ -183,8 +183,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
         with:
-          # Required because otherwise there are always changes detected when executing diff/rev-list
-          fetch-depth: 0
           # If no PAT is used the following error occurs on a push:
           # refusing to allow a GitHub App to create or update workflow `.github/workflows/xxx.yml` without `workflows` permission
           token: ${{ secrets.UPDATE_FROM_TEMPLATE_PAT }}
@@ -210,7 +208,7 @@ jobs:
 
             echo "Checking if update-branch-merged exists"
             git fetch
-            if [[ $(git ls-remote --exit-code --heads origin ${{ env.UPDATE_BRANCH_MERGED }}) ]]; then
+            if [[ $(git rev-parse origin/${{ env.UPDATE_BRANCH_MERGED }}) ]]; then
               echo "Branch origin/${{ env.UPDATE_BRANCH_MERGED }} is missing"
               exit 0
             fi
@@ -271,11 +269,8 @@ jobs:
           base_branch=$(git branch --show-current)
           echo "Base branch is $base_branch"
 
-          echo "Fully fetching..."
-          git fetch --unshallow || true
-          git config remote.origin.fetch "+refs/heads/*:refs/remotes/origin/*"
-          git fetch origin
-
+          echo "Fetching..."
+          git fetch
           if [[ $(git rev-parse origin/${{ env.UPDATE_BRANCH_MERGED }}) ]]; then
             echo "Branch origin/${{ env.UPDATE_BRANCH_MERGED }} is missing"
             exit 0