Changing search behavior in Pontoon's string list

[Matjaz Horvat]

Hi,

We just shipped a slight update to the way searching in the string list
works in Pontoon. Instead of triggering search automatically after the last
keystroke (with a 500 ms delay), pressing Enter is now required.

We believe this change will make searching less prone to typos and a little
bit faster, as well as consistent with search in the Machinery tab.

Thanks to everyone who provided feedback on Discourse and chat.mozilla.org!

Cheers,
Matjaž