Fixup last commit

Fixup last commit

Per https://github.com/joaotavora/eglot/issues/726.

I'm still not entirely convinced using all-completion here is a good
idea.  As usual the completion list we get from the server is
pre-filtered to whatever the server wishes.  Letting the completion
style do its own filtering (most completion styles use
completion-regexp-list and all-completions themselves) is completely
useless here.

Let's hope it's not harmful.

* eglot.el (eglot-completion-at-point): Fix all-completions call