fix ubuntu-latest stragglers

.github/workflows/build.yml

@@ -419,7 +419,7 @@ jobs:
         AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
       if: github.event_name == 'push' || (github.event_name == 'release' && (github.event.action == 'published' || github.event.action == 'rerequested'))
   build-xtensa:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     needs: test
     strategy:
       fail-fast: false

.github/workflows/create_website_pr.yml

@@ -10,7 +10,7 @@ on:
 
 jobs:
   website:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - name: Dump GitHub context
       env:

.github/workflows/pre-commit.yml

@@ -11,7 +11,7 @@ on:
 
 jobs:
   pre-commit:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
     - uses: actions/checkout@v1
     - uses: actions/setup-python@v1