Fix double XML encoding on Atom feed title

[somini]

This can be seen on the current Dilbert bridge, there's a title named:

Can't Succeed Within The Rules - Dilbert by Scott Adams

This title will disappear tomorrow, a new comic will take its place. :D

[somini]

The entryTitle is escaped again below:

https://github.com/RSS-Bridge/rss-bridge/pull/1247/files#diff-1258f65d50178d23aa3f9346fda10c01R69

[em92]

Nice catch!
Payed attention myself, that Html version does not double quote titles comparing to Atom version.
As example (see Ibb & obb):
html version: https://feed.eugenemolotov.ru/?action=display&bridge=Steam&userid=76561198260599288&only_discount=off&format=Html
atom: https://feed.eugenemolotov.ru/?action=display&bridge=Steam&userid=76561198260599288&only_discount=off&format=Atom
atom but fixed: https://feed.eugenemolotov.ru/dev/?action=display&bridge=Steam&userid=76561198260599288&only_discount=off&format=Atom

[teromene]

Nice catch !