Merge pull request #504 from hashicorp/ci-workflow

ci: limit workflow to PRs and specify conservative timeouts

.github/workflows/monorepo-validate.yaml

@@ -1,5 +1,5 @@
 name: Validate Monorepo
-on: [push]
+on: pull_request
 jobs:
 
   compliance:
@@ -39,6 +39,7 @@ jobs:
   lint:
     name: Lint
     runs-on: ubuntu-latest
+    timeout-minutes: 5
     steps:
       - uses: actions/checkout@v2
       - uses: actions/cache@v2
@@ -56,6 +57,7 @@ jobs:
   test:
     name: Test
     runs-on: ubuntu-latest
+    timeout-minutes: 15
     steps:
       - uses: actions/checkout@v2
       - uses: actions/cache@v2