1874: Handle blank language codes in the widget RPC

In the future these blank codes will be going away, but for now there are a few
hundred SubtitleLanguage's in our DB that have a language code of "".
Traditionally this meant "the original language of the video", so we'll just
make the name "Original" for now.

Done as part of Sentry Duty:
https://sentry.amara.org/amaraproduction/group/262/
Trailing whitespace.
Fix bad whitespace.
1875: Don't crash on notification to partners without settings

If a team belongs to a partner that doesn't have any notification settings, we
should just return instead of crashing and burning.

Done for Sentry Duty:
https://sentry.amara.org/amaraproduction/group/4137/
1738: Uncomment YT sync prompts for testing
Merge branch 'production' into staging
Updated integration repo
Merge branch 'production' into staging
1738: Styling tweak
Merge branch 'staging' into i-1738
1738: Fix logic for showing/hiding YT prompt for non-users
1738: Set the cookie path, duh.
1898: Created test case for transcription tasks when the video's original language is set
1898: If the video's audio (original) language is set, auto created transcribe tasks will be set on that language
Merge branch 'staging' of github.com:pculture/unisubs into i-1738
1738: Copy changes; add optimizely code
added missing pytz requirement
Merge branch 'staging' of github.com:pculture/unisubs into i-1738
Merge branch 'production' into staging
1738: More copy changes