Run connection hooks with proper dir-locals

Run connection hooks with proper dir-locals

eglot-connect-hook and eglot-server-initialized-hook must run in a
buffer with properly setup directory-local variables for the project.

This is crucial for things like eglot-signal-didChangeConfiguration,
which needs a properly setup value of eglot-workspace-configuration to
succeed.

I could have chosen any of the buffers where Eglot is activating
itself, but the approach using
hack-dir-local-variables-non-file-buffer seems more correct, despite
the name.

* eglot.el (eglot--connect): Run connection hooks with proper
dir-locals.

GitHub-reference: fix https://github.com/joaotavora/eglot/issues/196