Add debug.txt.1 to .gitignore (#9081)

This should have been done in #8904.
2019-11-02 19:29:14 +01:00 · 2019-11-02 19:29:14 +01:00 · 8697090b35
--- a/.gitignore
+++ b/.gitignore
@ -55,6 +55,7 @@ gtags.files
 ## Configuration/log files
 minetest.conf
 debug.txt
+debug.txt.1

 ## Other files generated by Minetest
 screenshot_*.png