[Backport to 4.0.x][Minor] Add autocomplete_fields to maps admin MapL…

[afabiani]

…ayer datasets (#10773)

(cherry picked from commit 50c67a5)

Conflicts:

geonode/maps/admin.py

Checklist

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[codecov]

Codecov Report

Merging #10812 (a44e3c4) into 4.0.x (69cafb0) will increase coverage by 19.51%.
The diff coverage is 100.00%.

❗ Current head a44e3c4 differs from pull request most recent head 5853f80. Consider uploading reports for the commit 5853f80 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##            4.0.x   #10812       +/-   ##
===========================================
+ Coverage   42.43%   61.95%   +19.51%     
===========================================
  Files         827      827               
  Lines       50916    50920        +4     
  Branches     6556     6556               
===========================================
+ Hits        21606    31545     +9939     
+ Misses      27979    17691    -10288     
- Partials     1331     1684      +353