Remove latest from the possible WP versions

Author: Rahe

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
     strategy:
       matrix:
         php_versions: [ '8.0', '8.1', '8.2', '8.3' ]
-        core: [ '6.0', '6.1', '6.2', '6.3', '6.4', '6.5', 'latest' ]
+        core: [ '6.0', '6.1', '6.2', '6.3', '6.4', '6.5' ]
     name: Test PHP ${{ matrix.php_versions }} with WP ${{ matrix.core }}
     steps:
     - name: Checkout