chore(fmt): format using stylua

Also fixed something in .stylua.toml that may cause stylua to fail, by
the way

lua/outline/providers/markdown.lua

@@ -27,7 +27,7 @@ function M.supports_buffer(bufnr, config)
       end
     end
   end
-  return ft == "markdown"
+  return ft == 'markdown'
 end
 
 -- Parses markdown files and returns a table of SymbolInformation[] which is
@@ -47,8 +47,8 @@ function M.handle_markdown()
       goto nextline
     end
 
-    local next_value = lines[line+1]
-    local is_emtpy_line = #value:gsub("^%s*(.-)%s*$", "%1") == 0
+    local next_value = lines[line + 1]
+    local is_emtpy_line = #value:gsub('^%s*(.-)%s*$', '%1') == 0
 
     local header, title = string.match(value, '^(#+)%s+(.+)$')
     if not header and next_value and not is_emtpy_line then

lua/outline/providers/nvim-lsp.lua

@@ -161,10 +161,12 @@ local function legacy_rename(sidebar, client, node)
   }
   local status, err
   if _G._outline_nvim_has[11] then
-    status, err = client:request_sync('textDocument/rename', params, request_timeout, sidebar.code.buf)
+    status, err =
+      client:request_sync('textDocument/rename', params, request_timeout, sidebar.code.buf)
   else
     ---@diagnostic disable-next-line
-    status, err = client.request_sync('textDocument/rename', params, request_timeout, sidebar.code.buf)
+    status, err =
+      client.request_sync('textDocument/rename', params, request_timeout, sidebar.code.buf)
   end
   if status == nil or status.err or err or status.result == nil then
     return false
@@ -236,7 +238,7 @@ function M.show_hover(sidebar)
 
   local md_lines = l.util.convert_input_to_markdown_lines(status.result.contents)
   if _G._outline_nvim_has[10] then
-    md_lines = vim.split(status.result.contents, '\n', { trimempty = true });
+    md_lines = vim.split(status.result.contents, '\n', { trimempty = true })
   else
     ---@diagnostic disable-next-line:deprecated
     md_lines = l.util.trim_empty_lines(md_lines)