build: #12 output coverage

Author: shaunthegeek

.git-pre-commit

@@ -6,4 +6,4 @@ for file in $FILES; do
   ./vendor/bin/phpcs --extensions=php --standard=PSR12 "$file"
   ./vendor/bin/phpmd "$file" text phpmd.xml
 done
-./vendor/bin/phpunit tests/
+XDEBUG_MODE=coverage ./vendor/bin/phpunit --coverage-text --coverage-filter=src/ tests/