[Fixes #7390] Fix parsing of style title from UserStyle.Title element

[afabiani]

References: #7390

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.

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• 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)
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[codecov]

Codecov Report

Merging #7405 (46f95d9) into master (9cb9991) will decrease coverage by 0.01%.
The diff coverage is 3.22%.

@@            Coverage Diff             @@
##           master    #7405      +/-   ##
==========================================
- Coverage   60.11%   60.10%   -0.02%     
==========================================
  Files         576      576              
  Lines       41348    41358      +10     
  Branches     5435     5436       +1     
==========================================
  Hits        24857    24857              
- Misses      14998    15008      +10     
  Partials     1493     1493