Update actions (#1363)

Signed-off-by: Knative Automation <automation@knative.team>

.github/workflows/knative-go-test.yaml

@@ -46,6 +46,16 @@ jobs:
 
       - name: Check out code
         uses: actions/checkout@v2
+        with:
+          fetch-depth: 0
+
+      - name: Merge upstream
+        if: github.event_name == 'pull_request'
+        run: |
+          git remote add upstream https://github.com/${{ github.repository }}.git
+          git fetch upstream ${{ github.base_ref }}
+          git pull --no-rebase --no-commit upstream ${{ github.base_ref }}
+        shell: bash
 
       - name: Check for .codecov.yaml
         id: codecov-enabled

.github/workflows/knative-stale.yaml

@@ -35,7 +35,7 @@ jobs:
           inactivity. Reopen the issue with `/reopen`. Mark the issue as
           fresh by adding the comment `/remove-lifecycle stale`.
         stale-issue-label: 'lifecycle/stale'
-        exempt-issue-labels: 'lifecycle/frozen'
+        exempt-issue-labels: 'lifecycle/frozen,triage/accepted'
 
         stale-pr-message: |-
           This Pull Request is stale because it has been open for 90 days with