chore: add E2E rollup job and exempt emdashbot from PR compliance (#132)

Add a rollup job that gates on all 8 E2E shards so it can be a single
required check. Exempt emdashbot from PR template validation alongside
dependabot and renovate.

.github/workflows/pr-compliance.yml

@@ -11,7 +11,7 @@ permissions:
 jobs:
   check-pr:
     name: Validate PR
-    if: github.actor != 'dependabot[bot]' && github.actor != 'renovate[bot]'
+    if: github.actor != 'dependabot[bot]' && github.actor != 'renovate[bot]' && github.actor != 'emdashbot[bot]'
     runs-on: ubuntu-latest
     steps:
       - name: Check PR template