Move skipBadPublishes() -> calculate-versions

[jablko]

Can we move skipBadPublishes() to the calculate-versions script, instead of calculating the incipient stub version from cached npm info twice, in generate-packages and publish-packages?

skipBadPublishes() calculates the version of the not-needed stub that we're about to publish. It depends on calculate-versions for cached npm-info. For regular packages, calculate-versions is where we actually perform that step (of figuring out the version we're about to publish).

What I did was:

• Move skipBadPublishes() to calculate-versions.ts. Combine it and isAlreadyDeprecated() into fetchIncipientStubVersion().
• Add that version to versions.json (the calculate-versions output), alongside the regular packages' versions-to-publish.
• Use it to replace skipBadPublishes() in generate-packages and publish-packages.

[jablko]

I've rebased this on #451 and added a couple of tests for fetchIncipientStubVersion(), similar to the tests for fetchTypesPackageVersionInfo() I propose adding in #464.

[sandersn]

With the new method of deprecation, I think the right thing is to remove skipBadPublishes entirely since it existed to skip the fallout from the publish/deprecate race condition on npm.

[jablko]

@sandersn Are there any other ways for a @types package version to get ahead of its not-needed version? The npm-naming rule should ensure we don't publish a minor version that doesn't already exist on npm, but there are some types in the repo from before that rule was a thing, e.g. angular-ui-router.

I can imagine some other ways in theory it could happen (the JS package adds types in a patch version and our patch version is already greater, they add types in a new major/minor but we publish a corresponding @types version before adding it to notNeededPackages.json).

You're right about removing skipBadPublishes() from publish-packages.ts since the new method of deprecation, but I wonder if its worth keeping for other cases?