Cleanup CI (#259)

- Test with PHP 8.3 only once.
- Remove redundant exif extension.

Author: kleisauke

.github/workflows/ci.yml

@@ -15,16 +15,15 @@ jobs:
           - php: '8.1'
           - php: '8.2'
           - php: '8.3'
-          - php: '8.3'
           - php: '8.4'
 
     steps:
       - name: Setup PHP
         uses: shivammathur/setup-php@v2
         with:
           php-version: ${{ matrix.php }}
-          ini-values: zend.max_allowed_stack_size=-1,ffi.enable=true
-          extensions: ffi, exif
+          ini-values: ffi.enable=true, zend.max_allowed_stack_size=-1
+          extensions: ffi
           tools: composer:v2
           coverage: none