[Fixes #10462] GeoNode is vulnerable to an XML External Entity (XXE) injection

[afabiani]

References: #10462

Checklist

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[codecov]

Codecov Report

Merging #10463 (df1409a) into master (14a7032) will increase coverage by 0.00%.
The diff coverage is 77.77%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #10463   +/-   ##
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  Coverage   61.94%   61.95%           
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  Files         827      827           
  Lines       50900    50904    +4     
  Branches     6551     6551           
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+ Hits        31532    31538    +6     
+ Misses      17686    17683    -3     
- Partials     1682     1683    +1