Ignore submodule updates on engine version (#44533)

Listen the error annoyed me okay.

.github/workflows/no-submodule-update.yml

@@ -10,5 +10,22 @@ jobs:
     name: Submodule update in pr found
     runs-on: ubuntu-latest
     steps:
-      - name: Fail
-        run: exit 1
+      - uses: actions/checkout@v7
+        with:
+          fetch-depth: 0
+
+      - name: Check changed files
+        shell: pwsh
+        run: |
+          $changedFiles = @(git diff --name-only "${{ github.event.pull_request.base.sha }}" "${{ github.event.pull_request.head.sha }}")
+
+          if ($changedFiles.Count -eq 1 -and $changedFiles[0] -eq "RobustToolbox") {
+            Write-Host "Only RobustToolbox was changed; allowing standalone submodule update."
+            exit 0
+          }
+
+          Write-Host "RobustToolbox was updated alongside other files:"
+          foreach ($file in $changedFiles) {
+            Write-Host " - $file"
+          }
+          exit 1