Remove useless call in lsp part

lua/hardline/parts/lsp.lua

@@ -1,7 +1,6 @@
-local lsp, vim = vim.lsp, vim
+local lsp = vim.lsp
 
 local function get_diagnostic(prefix, severity)
-  if vim.tbl_isempty(lsp.buf_get_clients(0)) then return '' end
   local count = lsp.diagnostic.get_count(0, severity)
   if count < 1 then return '' end
   return string.format('%s:%d', prefix, count)