Update determine runner workflow to use large runners if the branch name matches the rc branching format (#846)

**Context:**
This PR introduces a change to the CI, where a PR that matches the
naming format of the RC branches (eg: `vX.Y.Z-rcN`) is automatically
on-boarded to use large runner queue *without the usage of a label*

**Description of the Change:**
This change has been introduced within pennylane-lightning with the
following two PRs:
- PennyLaneAI/pennylane-lightning#769
- PennyLaneAI/pennylane-lightning#774

**Benefits:**
Lower wait times for rc branch builds

**Possible Drawbacks:**
As noted in the lightning PRs, though the runners have parity, it is
possible for a workflow to fail on the larger runners. The `urgent`
label will be added to this PR to ensure jobs pass.

**Related GitHub Issues:**

Author: rashidnhm

.github/workflows/determine-workflow-runner.yml

@@ -33,8 +33,17 @@ jobs:
         if: >-
           ${{
             github.event_name == 'pull_request'
-            && contains(github.event.pull_request.labels.*.name, 'urgent')
             && startsWith(inputs.default_runner, 'ubuntu')
           }}
         id: runner_group
-        run: echo "runner_group=$LARGE_RUNNER_GROUP_NAME" >> $GITHUB_OUTPUT
+        env:
+          # We are not able to use \d to check numeric values as bash does not allow them (not POSIX compliant)
+          RC_BRANCH_FORMAT_REGEX: v[0-9]+\.[0-9]+\.[0-9]+-rc[0-9]?
+          REPO_FULL_NAME: PennyLaneAI/catalyst
+        run: |
+          if [[ '${{ contains(github.event.pull_request.labels.*.name, 'urgent') }}' == 'true' || ('${{ github.event.pull_request.head.repo.full_name }}' == "$REPO_FULL_NAME" && '${{ github.event.pull_request.head.ref }}' =~ $RC_BRANCH_FORMAT_REGEX) ]]; then
+            echo "This job requires usage of the large runner group '$LARGE_RUNNER_GROUP_NAME'";
+            echo "runner_group=$LARGE_RUNNER_GROUP_NAME" >> $GITHUB_OUTPUT
+          else
+            echo "This job does not require usage of large runners ...";
+          fi