feat(health): improvements to :checkhealth #40935

Changes:
- Removed the blank line before the first healthcheck header.
- Fixed a bug where the entire "Terminal" section of `vim.health` would
  not appear if the `infocmp` executable was not found.
- Fixed a typo in `vim.lsp` when displaying the LSP log level.

runtime/lua/vim/lsp/health.lua

@@ -24,7 +24,7 @@ local function check_log()
   local log = vim.lsp.log
   local current_log_level = log.get_level()
   local log_level_string = log.levels[current_log_level] ---@type string
-  report_info(string.format('LSP log level : %s', log_level_string))
+  report_info(string.format('LSP log level: %s', log_level_string))
 
   if current_log_level < log.levels.WARN then
     report_warn(