binding.gyp: Use C++ 14 for Electron 11 support

[DeeDeeG]

Quick Summary

Electron 11 has a newer V8 engine, which apparently requires building with C++ 14 or newer.

This Pull Request bumps the C++ standard in binding.gyp so node-gyp will compile it in a way that is compatible with Electron 11.

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Identify the Bug

Helps with atom/atom#22687, see other modules that needed this same bump: atom/atom#22687 (comment)

Description of the Change

In binding.gyp (which is read and interpreted by node-gyp), specify that compilers should use the C++ 14 standard when compiling this module's native C++ code, rather than the older C++ 11 standard that is no-longer supported in the latest V8 JS engine. Electron 11 comes with a newer V8 version.

I gathered most of this information from the comments in this issue: electron/electron#26364

Alternate Designs

We could bump to an even newer C++ standard (C++ 17, C++ 20)

Possible Drawbacks

None

Verification Process

Allows Atom CI to proceed past building this package. See my CI runs: https://dev.azure.com/DeeDeeG/b/_build?definitionId=15&_a=summary&branchFilter=182%2C182%2C182%2C182%2C182%2C182

• Before: https://dev.azure.com/DeeDeeG/b/_build/results?buildId=1175 (error during bootstrapping on macOS, upon trying to build @atom/nsfw.)
• After: https://dev.azure.com/DeeDeeG/b/_build/results?buildId=1176 (bootstrapping on macOS gets a little further, failing on a different package.)

Release Notes

Compile as C++ 14 for compatibility with Electron 11