ruTorrent: Upgrade to v5.1.1

# ruTorrent v5.1.1
**This is a critical hotfix. It's highly recommended to upgrade.** It resolves a bug with tracker announce groups when creating torrents. It also fixes incorrect setting of the side panel min width. The `v5.1` release is ultra stable and will receive long term support. 

## What's Changed
* Fix typo in resizeLeft function by jevenski in Novik/ruTorrent#2807
* Fix create torrent announce group by jevenski in Novik/ruTorrent#2811

**Full Changelog**: Novik/ruTorrent@v5.1.0...v5.1.1

Dockerfile

@@ -7,8 +7,8 @@ ARG XMLRPC_VERSION=01.58.00
 ARG MKTORRENT_VERSION=v1.1
 ARG GEOIP2_PHPEXT_VERSION=1.3.1
 
-# v5.1.0
-ARG RUTORRENT_VERSION=84a98bfdd4380319fa1cac0a08ec8b137c494f72
+# v5.1.1
+ARG RUTORRENT_VERSION=12eb2cfba5846714cc9909865ceba3a7c1db0de7
 ARG GEOIP2_RUTORRENT_VERSION=4ff2bde530bb8eef13af84e4413cedea97eda148
 ARG DUMP_TORRENT_VERSION=302ac444a20442edb4aeabef65b264a85ab88ce9