policy: fix actual bug

Author: aduh95

lib/internal/process/pre_execution.js

@@ -589,7 +589,7 @@ function readPolicyFromDisk() {
     // no bare specifiers for now
     let manifestURL;
     if (require('path').isAbsolute(experimentalPolicy)) {
-      manifestURL = new URL(`file://${experimentalPolicy}`);
+      manifestURL = pathToFileURL(experimentalPolicy);
     } else {
       const cwdURL = pathToFileURL(process.cwd());
       cwdURL.pathname += '/';