lsp: Do not drop lsp buffer handle from editor when a language change leads to buffer having a legit language (#44469)

Fixes a bug that led to us unnecessarily restarting a language server
when we were looking at a single file of a given language.

Release Notes:

- Fixed a bug that led to Zed sometimes starting an excessive amount of
language servers
3180f44477Piotr Osiewicz committed on 12/9/2025, 8:37:39 PM· committed by GitHubparent5dd8561
10 files changedLine totals unavailable