compute-baseline: Use JSON import attribute when importing BCD

[ddbeck]

I think this will fix the issue reported by @tidoust in #967 (comment).

This change will require one of Node.js v16.14.0+ (see #1051 (comment)), v18.20.0+, or v20.10.0+.

If you want to test this immediately, do the following:

1. Check out this PR's branch.
2. Run npm pack --workspace compute-baseline. A .tgz file for the package is built.
3. In your project, install the .tgz file. For example, run npm install ../path/to/compute-baseline-0.1.0.tgz.

[tidoust]

That seems a good start but there are other import statements that need the same treatment at the top of other files: browser.ts, feature.ts, supportStatements.ts, release.ts, typeUtils.ts, walk.ts.

Also, I don't think that will work with v16.x (the syntax then used assert instead of with) but that's probably fine?

[ddbeck]

That seems a good start but there are other import statements that need the same treatment at the top of other files: browser.ts, feature.ts, supportStatements.ts, release.ts, typeUtils.ts, walk.ts.

The other imports are TypeScript type imports. When TypeScript compiles, these statements are not emitted into the final .js files. Adding import attributes to those imports would have no effect on the built package.

Also, I don't think that will work with v16.x (the syntax then used assert instead of with) but that's probably fine?

Ah, I made a mistake in my original description—import attributes were never backported to Node 16. I think this is OK though, since v16 has been EOL since September of last year.