Don't display main KeePass window when requesting unlock

[lopsided98]

Currently, when a trigger unlock request is sent to keepasshttp, it opens the main window as well as the unlock dialog. This behavior can be stopped by deleting lines 340-343 of KeePass.cs

I use keepasshttp along with python3-keepasshttp to automate password entry for a number of applications and having to close the window after entering the database password is very annoying.

I can't think of a reason someone would want this behavior, but if there is a need for it, this feature could possibly be made optional in the KeePassHttp settings or in the protocol requests.