Allow usage of environmental variables in extraFiles and extraResources

[liusy182]

• Version: 14.1.1

• Target: Windows

I have a electron native module that integrates with a third party library. The third party library has different configurations (x86 v.s. x64, Debug v.s. Release). I am thinking if it is a good idea to have electron-builder's extraFiles and extraResources accept file path with environmental variables. For example,

 "extraFiles": [{
      "from": "third_party/%PLATFORM%/%DEBUG_RELEASE%",
      "to": "./"
    }],

If I set env PLATFORM to x86 and DEBUG_RELEASE to Release. I want the files in third_party/x86/Debug to be copied to ./.

Right now I can workaround this by having another script that modifies package.json based on different configurations.

[develar]

${env.ENV_NAME} — any environment variable.

[liusy182]

That is fast. Thanks a lot !