fix abs path check

Author: swissspidy

src/Context/ThenStepDefinitions.php

@@ -455,8 +455,10 @@ public function then_stdout_stderr_should_be_a_specific_version_string( $stream,
 	public function then_a_specific_file_folder_should_exist( $path, $type, $strictly, $action, $expected = null ): void {
 		$path = $this->replace_variables( $path );
 
+		$is_absolute = preg_match( '#^[a-zA-Z]:\\\\#', $path ) || ( '/' === $path[0] || '\\' === $path[0] );
+
 		// If it's a relative path, make it relative to the current test dir.
-		if ( DIRECTORY_SEPARATOR !== $path[0] && 0 !== strpos( $path, $this->variables['RUN_DIR'] ) ) {
+		if ( ! $is_absolute ) {
 			$path = $this->variables['RUN_DIR'] . DIRECTORY_SEPARATOR . $path;
 		}