chore: pin ubuntu version in GitHub Actions (#8375)

Author: sissbruecker

.github/workflows/coverage.yml

@@ -12,7 +12,7 @@ permissions:
 jobs:
   tests:
     name: Unit tests
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:

.github/workflows/unit-tests.yml

@@ -8,7 +8,7 @@ permissions:
 jobs:
   chrome:
     name: Chrome
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:
@@ -27,7 +27,7 @@ jobs:
         run: yarn test
   firefox:
     name: Firefox
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:
@@ -49,7 +49,7 @@ jobs:
         run: yarn test:firefox
   webkit:
     name: WebKit
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:

.github/workflows/verify.yml

@@ -8,7 +8,7 @@ permissions:
 jobs:
   lint:
     name: Lint
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
 
@@ -31,7 +31,7 @@ jobs:
         run: yarn lint:types
   snapshots:
     name: Snapshot tests
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:
@@ -50,7 +50,7 @@ jobs:
         run: yarn test:snapshots
   integration:
     name: Integration tests
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     steps:
       - uses: actions/checkout@v4
         with:

.github/workflows/visual-tests.yml

@@ -8,7 +8,7 @@ permissions:
 jobs:
   lumo:
     name: Lumo
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.repository_owner == 'vaadin'
 
     steps:
@@ -45,7 +45,7 @@ jobs:
             packages/vaadin-lumo-styles/test/visual/screenshots/failed/*.png
   material:
     name: Material
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-22.04
     if: github.repository_owner == 'vaadin'
 
     steps: