Fix getEnv not using getOptionalEnvVarFrom

lib/entry-points.js

@@ -148663,7 +148663,7 @@ function initializeEnvironment(version) {
 function getEnv(env = process.env) {
   return {
     getRequired: (name) => getRequiredEnvVar(env, name),
-    getOptional: (name) => getOptionalEnvVar(name)
+    getOptional: (name) => getOptionalEnvVarFrom(env, name)
   };
 }
 function getRequiredEnvVar(env, paramName) {