GenLSP.Test.server/2 cannot be isolated properly

[sineed]

I faced with it while I wanted to extract tests for hover feature in NextLS to a dedicated test file (as tests in one file and not wrapped in different modules are processing sequentially).
I reached the point when GenLSP.Buffer couldn't be started as there is already one existing. But forwarding unique name to it didn't work because the @options_schema accepts only communication.

After fixing this other isolation problems may arise.

[mhanberg]

So the fix is

when starting the buffer, the Keyword.get(opts, :name, __MODULE__) should be Keyword.take(opts, [:name]) instead

and the @options_schema in GenLSP should not have a default for :buffer

then in NextLS and Credo Language Server, in the supervision tree, Buffer should be given a name and that should be passed into the GenLSP process

[mhanberg]

this will be a breaking change, so for whomever implements this, your commit should be fix!: blah blah