[heft] Update node-sass to support node 15.

[halfnibble]

Summary

Update node-sass to support Node 15.

Details

Fixes #2490
Note: Loses heft sass support for Node versions 8, 11, and 13.

How it was tested

Tested with build-tests/heft-sass-test

[chengcyber]

Kind of curious about whether it is possible to use sass (Dart Sass) package instead of node-sass. Since node-sass has been deprecated.

[halfnibble]

Kind of curious about whether it is possible to use sass (Dart Sass) package instead of node-sass. Since node-sass has been deprecated.

Probably. Last time I tried dart sass it was about 3x slower than libsass. I've actually mulled the idea of forking node-sass and creating my own open source library. There are some features I want in Sass that the maintainers don't seem too keen on. But alas, I doubt I have the time.

[dmichon-msft]

There's a recommendation that Dart Sass is faster than node-sass if you get the version that runs the Dart VM, but that one doesn't ship as an npm package.

[xc2]

How about using sass@npm instead of node-sass@npm in rushstack by default, and providing options for user to specific render function or sass package.

[halfnibble]

How about using sass@npm instead of node-sass@npm in rushstack by default, and providing options for user to specific render function or sass package.

We are going to refactor this Heft plugin and make the entire sass plugin both optional (many node projects don't need Sass) and configurable. I'll create a separate issue to track that endeavor. As a quick fix, however, I will get this version bump in as is.