Update integration.yml to remove Drupal 8.9 (#34)

Removed Drupal version 8.9 from the CI matrix.

Author: mglaman

.github/workflows/integration.yml

@@ -19,8 +19,6 @@ jobs:
       fail-fast: false
       matrix:
         include:
-          - php-version: "7.4"
-            drupal-version: "~8.9"
           - php-version: "7.4"
             drupal-version: "^9"
           - php-version: "8.0"