Fix escaped environment variables in script.

lib/main.js

@@ -84,7 +84,7 @@ function run() {
             // execute the custom script
             try {
                 for (const script of scripts) {
-                    yield exec.exec(`${script}`);
+                    yield exec.exec(`sh -c \\"${script}"`);
                 }
             }
             catch (error) {