Move benchmarks into dedicated NPM workspace

[jonkoops]

Moves the classnames-benchmarks package into an NPM workspace containing all of it's own dependencies, and creates aliases for the local and last published NPM version in the package, removing the need to provide a relative path, and reducing the need for additional NPM installs.

[dcousens]

LGTM

[KennanChan]

It seems that this PR causes yarn to warn about "Workspaces can only be enabled in private projects.".

[jonkoops]

It seems that this PR causes yarn to warn about "Workspaces can only be enabled in private projects.".

Don't use Yarn for this project, it has been set up to work with NPM, it's also the only package manager a lockfile is checked in for.

[KennanChan]

'Classnames' is actually an indirect dependency of my project. I managed to bypass this warning by setting workspaces-experimental false in yarnrc.

[dcousens]

@jonkoops the package.json is published though?

[jonkoops]

the package.json is published though?

Correct, but workspaces should have no influence on that as far as I know. Not sure what is going on here, will do some research.

[jonkoops]

I am able to reproduce this, seem like this is a bug in Yarn (yarnpkg/yarn#8580) only present if you use v1 of Yarn, which is unfortunately still the default. When updating to the latest version of Yarn, this problem goes away.

[jonkoops]

@KennanChan this should now be fixed by #350 as soon as the release for v2.5.1 goes through.