src: fix loadEnvFile ENOENT error

Before this change the error message for `process.loadEnvFile()` without
an `.env` file present in the current working directory was looking like
this: `ENOENT: .env, Failed to load '%s'.` This obviously isn't what the
author intended.

To fix that, just return a "plain" ENOENT open error. It should be
descriptive enough. That means for the above example, the error message
is now `ENOENT: no such file or directory, open '.env'`.

Author: fahrradflucht

src/node_process_methods.cc

@@ -492,7 +492,7 @@ static void LoadEnvFile(const v8::FunctionCallbackInfo<v8::Value>& args) {
       break;
     }
     case dotenv.ParseResult::FileError: {
-      env->ThrowUVException(UV_ENOENT, "Failed to load '%s'.", path.c_str());
+      env->ThrowUVException(UV_ENOENT, "open", nullptr, path.c_str());
       break;
     }
     default:

test/parallel/test-process-load-env-file.js

@@ -45,13 +45,13 @@ describe('process.loadEnvFile()', () => {
   it('should throw when file does not exist', async () => {
     assert.throws(() => {
       process.loadEnvFile(missingEnvFile);
-    }, { code: 'ENOENT' });
+    }, /ENOENT: no such file or directory, open '.*non-existent-file\.env'/);
   });
 
   it('should throw when `.env` does not exist', async () => {
     assert.throws(() => {
       process.loadEnvFile();
-    }, { code: 'ENOENT' });
+    }, /ENOENT: no such file or directory, open '\.env'/);
   });
 
   it('should check for permissions', async () => {