fix: Lsp[Stop/Restart] fix

[Atan-D-RP4]

Problem:
0d90bb9 broke Lsp[Stop/Restart] due accessing vim.lsp.config with potentially nil/invalid name with vim.lsp.config[name] in the case of #clients == 0 being false.

Fix:
Just added an else clause that makes the clients variable a vim.lsp.Clients[] instead list/table of str's.

fix #4153

[justinmk]

@superatomic do you see a way to address this without 20 lines of new code ?

[superatomic]

Oops! I completely forgot to test the modified commands with arguments. Sorry for breaking master.

@superatomic do you see a way to address this without 20 lines of new code ?

There's one way to do this: revert most of the changes I made in #4140, but replace client:stop(true) with vim.iter(vim.lsp.get_clients({ name = name })):each(function(client) client:stop(true) end). This allows for stopping a client by name, instead of changing the code to require a client. I can open a PR with these changes if you would prefer that to this current one.