Support ESM forge.config.js

[mahnunchik]

Pre-flight checklist

• I have read the contribution documentation for this project.
• I agree to follow the code of conduct that this project uses.
• I have searched the issue tracker for a feature request that matches the one I want to file, without success.

Problem description

As ESM will lended in electron 28 electron/electron#37535 (comment) so it is useful to have ESM support in forge.config.js

Proposed solution

ESM support ;)

Alternatives considered

I don't know any reason to not support ESM

Additional information

No response

[mahnunchik]

Error [ERR_REQUIRE_ESM]: require() of ES Module /test-electron/forge.config.js from /test-electron/node_modules/@electron-forge/core/dist/util/forge-config.js not supported.
Instead change the require of forge.config.js in /test-electron/node_modules/@electron-forge/core/dist/util/forge-config.js to a dynamic import() which is available in all CommonJS modules.

According to the error message adding the ESM support should be pretty easy.

[mahnunchik]

Monkey patch of this file makes ESM config works!

const loaded = await import(path_1.default.resolve(dir, forgeConfig));