ci: update to use ubuntu-latest runners

The commit updates CI to replace usages of `ubuntu-18.04` which is
deprecated and soon to be removed, and instead opts to use
`ubuntu-latest`. The changes also align `ubuntu-latest` across the repo.

Signed-off-by: vince-fugnitto <vincent.fugnitto@ericsson.com>

Author: vince-fugnitto

.github/workflows/ci-cd.yml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [windows-2019, ubuntu-18.04, macos-11]
+        os: [windows-2019, ubuntu-latest, macos-11]
         node: [14.x, 16.x]
 
     runs-on: ${{ matrix.os }}
@@ -105,7 +105,7 @@ jobs:
   publish:
     needs: build
     if: github.ref == 'refs/heads/master' && github.event_name != 'schedule' # We still publish the manually dispatched workflows: 'workflow_dispatch'.
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
 
     # The current approach is silly. We should be smarter and use `actions/upload-artifact` and `actions/download-artifact` instead of rebuilding
     # everything from scratch again. (git checkout, Node.js install, yarn, etc.) It was not possible to share artifacts on Travis CI without an

.github/workflows/license-check.yml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-18.04]
+        os: [ubuntu-latest]
         node: ['16.x']
         java: ['11']
 

.github/workflows/playwright.yml

@@ -13,9 +13,9 @@ on:
 
 jobs:
   build-and-test-playwright:
-    name: ubuntu-18.04,  Node.js 16.x
+    name: ubuntu-latest,  Node.js 16.x
 
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-latest
     timeout-minutes: 60
 
     steps:

.github/workflows/set-milestone-on-pr.yml

@@ -22,7 +22,7 @@ on:
 jobs:
   set-milestone:
     if: github.event.pull_request.merged == true
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
       - name: Checkout code
         uses: actions/checkout@v2