Language Tagging autocomplete is very slow.

[richmanrachel]

Describe the bug
Despite relatively few languages in our database, adding language information in the admin site is slow and oddly laborious. Other drop down menus/auto-complete boxes are much faster, so this bug is to track the specificities of the languages (Primary and Secondary).

To reproduce
Steps to reproduce the behavior:

1. Go to a document detail page in the admin site
2. Type "Hebrew" into Primary Languages. Rachel was able to type out the whole word and had to wait an additional 3 seconds before Hebrew came up as an option.

Expected behavior
Hebrew to pop up after "He"

Device information

• Device: MacBook Pro Air
• OS and version: macOS 12.0.1
• Browser and version: Chrome Version 101.0.4951.54
• Site version 4.4.1

Additional context
@rlskoeser noted in #725: "I think it's using the annotated query we use for the list view that generates counts of documents associated with each language. Let's open a separate bug to track the slowness specifically and I'll see if I can get the autocomplete search to use a different queryset."

[richmanrachel]

Much better! Thank you!