[Fixes #12858] Fixed missing translations for facets labels

[giohappy]

Checklist

Reviewing is a process done by project maintainers, mostly on a volunteer basis. We try to keep the overhead as small as possible and appreciate if you help us to do so by completing the following items. Feel free to ask in a comment if you have troubles with any of them.

For all pull requests:

• Confirm you have read the contribution guidelines
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The following are required only for core and extension modules (they are welcomed, but not required, for contrib modules):

• There is a ticket in https://github.com/GeoNode/geonode/issues describing the issue/improvement/feature (a notable exemption is, changes not visible to end-users)
• The issue connected to the PR must have Labels and Milestone assigned
• PR for bug fixes and small new features are presented as a single commit
• Commit message must be in the form "[Fixes #<issue_number>] Title of the Issue"
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• New unit tests have been added covering the changes, unless there is an explanation on why the tests are not necessary/implemented
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• Commits adding new texts do use gettext and have updated .po / .mo files (without location infos)

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 67.97%. Comparing base (5eaad8a) to head (5afc71b).
Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #12859   +/-   ##
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  Coverage   67.97%   67.97%           
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  Files         977      977           
  Lines       59040    59045    +5     
  Branches     6897     6897           
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+ Hits        40132    40137    +5     
  Misses      17266    17266           
  Partials     1642     1642