Rename 8.x branch to 8.19 (#4337)

Author: pquentin

.github/workflows/update-rest-api-json.yml

@@ -13,7 +13,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        branch: ['main', '9.0', '8.x', '8.18', '8.17', '8.16', '7.17']
+        branch: ['main', '9.0', '8.19', '8.18', '8.17', '8.16', '7.17']
 
     steps:
       - uses: actions/checkout@v4

.github/workflows/validate-pr.yml

@@ -4,7 +4,6 @@ on:
   pull_request:
     branches:
       - main
-      - 8.x
       - '[0-9]+.[0-9]+'
 
 jobs: