[TOOLING][TESTS] Allow specifying any phpunit flag when invoking make

Examples:
  make test -- --filter 'method'
  make test -- directory

docker/tooling/coverage.sh

@@ -10,5 +10,5 @@ if [ "$#" -eq 0 ] || [ -z "$*" ]; then
     vendor/bin/simple-phpunit -vvv --coverage-html .test_coverage_report
 else
     echo "Running with filter"
-    vendor/bin/simple-phpunit -vvv --coverage-html .test_coverage_report --filter "$*"
+    vendor/bin/simple-phpunit -vvv --coverage-html .test_coverage_report $*
 fi