Update runtime files

runtime/pack/dist/opt/termdebug/plugin/termdebug.vim

@@ -2,7 +2,7 @@
 "
 " Author: Bram Moolenaar
 " Copyright: Vim license applies, see ":help license"
-" Last Change: 2021 Dec 16
+" Last Change: 2022 Jan 13
 "
 " WORK IN PROGRESS - Only the basics work
 " Note: On MS-Windows you need a recent version of gdb.  The one included with
@@ -1252,8 +1252,17 @@ func s:HandleCursor(msg)
   if a:msg =~ '^\(\*stopped\|=thread-selected\)' && filereadable(fname)
     let lnum = substitute(a:msg, '.*line="\([^"]*\)".*', '\1', '')
     if lnum =~ '^[0-9]*$'
-    call s:GotoSourcewinOrCreateIt()
+      call s:GotoSourcewinOrCreateIt()
       if expand('%:p') != fnamemodify(fname, ':p')
+	augroup Termdebug
+	  " Always open a file read-only instead of showing the ATTENTION
+	  " prompt, since we are unlikely to want to edit the file.
+	  " The file may be changed but not saved, warn for that.
+	  au SwapExists * echohl WarningMsg
+		\ | echo 'Warning: file is being edited elsewhere'
+		\ | echohl None
+		\ | let v:swapchoice = '0'
+	augroup END
 	if &modified
 	  " TODO: find existing window
 	  exe 'split ' . fnameescape(fname)
@@ -1262,6 +1271,9 @@ func s:HandleCursor(msg)
 	else
 	  exe 'edit ' . fnameescape(fname)
 	endif
+	augroup Termdebug
+	  au! SwapExists
+	augroup END
       endif
       exe lnum
       normal! zv