[Fixes #10936] Implement a generic API endpoint for linked resources

[mattiagiupponi]

ref #10936

The API is filterable:

• If the filter is related to the resource which we are asking the linked_resource we can use the dynamic filter example:

With the below URL, the filter will refer to the information of the resource PK and not to the linked resource. This is due to the behavior of the dynamic filter that geonode uses. We cannot change this

URL: /api/v2/{PK}/linked_resources?filter{resource_type}=map

With the below URL, the filter will refer to the linked resource. The filter accepts the default django queryset filtering

URL: /api/v2/{PK}/linked_resources?resource_type=map
URL: /api/v2/{PK}/linked_resources?title__icontains=title
URL: /api/v2/{PK}/linked_resources?resource_type=map

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[codecov]

Codecov Report

Merging #10941 (45397ec) into master (2f12608) will increase coverage by 0.07%.
The diff coverage is 94.95%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #10941      +/-   ##
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+ Coverage   62.22%   62.30%   +0.07%     
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  Files         828      828              
  Lines       51252    51367     +115     
  Branches     6564     6573       +9     
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+ Hits        31891    32002     +111     
- Misses      17666    17668       +2     
- Partials     1695     1697       +2