Correctly exclude unsupported WP, PHP combinations.

Author: peterwilsoncc

.github/workflows/phpunit.yaml

@@ -24,10 +24,16 @@ jobs:
         wp-versions: [ '6.3', '6.4', '6.5', '6.6', '6.7', '6.8', 'latest', 'trunk' ]
         php-versions: ['7.4', '8.0', '8.1', '8.2', '8.3', '8.4' ]
         exclude:
-          - php-versions: '8.3'
-            wp-versions: '6.3'
-          - php-versions: '8.4'
-            wp-versions: [ '6.3', '6.4', '6.5', '6.6' ]
+          - wp-versions: '6.3'
+            php-versions: '8.3'
+          - wp-versions: '6.3'
+            php-versions: '8.4'
+          - wp-versions: '6.4'
+            php-versions: '8.4'
+          - wp-versions: '6.5'
+            php-versions: '8.4'
+          - wp-versions: '6.6'
+            php-versions: '8.4'
     name: WP ${{ matrix.wp-versions }} / PHP ${{ matrix.php-versions }}
 
     steps: