chore: warn when nodeIntegration's default is relied on

[nornagon]

Description of Change

nodeIntegration will be disabled by default in Electron 5.0. This adds a warning for users of 4.0 to help prepare for the change.

Checklist

• PR description included and stakeholders cc'd
• PR title follows semantic commit guidelines

Release Notes

Notes: in Electron 5.0, the default for nodeIntegration will change from true to false. Electron 4 will log a warning in the renderer when nodeIntegration is enabled by default.

[zcbenz]

Tested the code and it works perfectly.

[release-clerk]

Release Notes Persisted

in Electron 5.0, the default for nodeIntegration will change from true to false. Electron 4 will log a warning in the renderer when nodeIntegration is enabled by default.