ci: drop PHP 8.2 from PHPUnit matrix as server master requires PHP 8.3

Signed-off-by: Oleksander Piskun <oleksandr2088@icloud.com>

Author: oleksandr-nc

.github/workflows/phpunit.yml

@@ -22,7 +22,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        php-version: ['8.2', '8.3']
+        php-version: ['8.3']
         server-version: ['master']
 
     steps: