[Fixes #4959] By using UPLOADER=geonode.rest we are facing a timing i…

[afabiani]

…ssues on signals

Checklist

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[codecov]

Codecov Report

Merging #4960 into master will not change coverage.
The diff coverage is 0%.

@@           Coverage Diff           @@
##           master    #4960   +/-   ##
=======================================
  Coverage   59.88%   59.88%           
=======================================
  Files         231      231           
  Lines       12418    12418           
  Branches     1797     1797           
=======================================
  Hits         7437     7437           
  Misses       4366     4366           
  Partials      615      615

[capooti]

Great work @afabiani it seems all good to me!
I am going to merge this and will test it on two different instances which have a large number of layers and let you know