fix(package): pass missing user-defined hooks to packager

[erikian]

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• I agree to follow the code of conduct that this project follows, as appropriate.
• The changes are appropriately documented (if applicable).
• The changes have sufficient test coverage (if applicable).
• The testsuite passes successfully on my local machine (if applicable).

Summarize your changes:

Currently, afterComplete hooks defined in the Forge configuration are not being passed to electron-packager, so the following code has no effect:

const forgeConfig = {
  packagerConfig: {
    afterComplete: [
      async (buildPath, electronVersion, packagedPlatform, packagedArch, done) => {
        // some code...

        done();
      },
    ],
  },
};

The existing tests for hooks cover only Forge-specific hooks, not hooks from electron-packager, so I didn't add any tests.

[erikian]

There were other hooks not being passed to packager, so I've added them too

[jhetuts]

There were other hooks not being passed to packager, so I've added them too

Is the afterCopy hook is one of those?

[erikian]

@jhetuts no, afterComplete is the only hook not being passed