how to make wrangler use yarn instead of npm?

[weiklr]

Hi,
I noticed that wrangler uses npm out of the box, but my github actions workflow is using yarn. Is there some flag that i can set to make wrangler use yarn instead?

I do notice there's a 'packageManager' variable in the source code. can that be used for this purpose?

[Hugo-C]

README now have a paragraph about it.