[IMPROVEMENT] Use django-filters for api filtering

[kfdm]

• Filter shard by name /api/shard?name=
• Filter service by name, shard /api/service?name=&shard=
• Filter project by name, shard, service /api/project?name=&shard=&service=

[codecov-io]

Codecov Report

Merging #126 into master will increase coverage by 0.33%.
The diff coverage is 93.93%.

@@            Coverage Diff             @@
##           master     #126      +/-   ##
==========================================
+ Coverage   46.34%   46.68%   +0.33%     
==========================================
  Files          39       40       +1     
  Lines        2451     2455       +4     
==========================================
+ Hits         1136     1146      +10     
+ Misses       1315     1309       -6

Impacted Files	Coverage Δ
promgen/settings.py	0% <ø> (ø)	⬆️
promgen/filters.py	100% <100%> (ø)
promgen/rest.py	61.11% <100%> (+2.28%)	⬆️
promgen/serializers.py	94.44% <86.66%> (+10.77%)	⬆️

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