Added filters to agent resolver

[crisely09]

This is related to this comment: https://github.com/BlueBrain/nexus-forge/commit/051eb73d2091c2cecccdf54358f4980b8e876959#commitcomment-117123788 The ontology resolver was not updated when the filters were added, so it breaks when calling the function get_context

• Added filters to the call in the agent resolver
• changed the way that filters are defined to avoid KeyErrors

[codecov-commenter]

Codecov Report

Merging #312 (c54d1a5) into master (85bf44c) will not change coverage. The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master     #312   +/-   ##
=======================================
  Coverage   72.63%   72.63%           
=======================================
  Files          88       88           
  Lines        5627     5627           
=======================================
  Hits         4087     4087           
  Misses       1540     1540           

Flag	Coverage Δ
unittests	72.63% <0.00%> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
...gforge/specializations/resolvers/agent_resolver.py	57.50% <0.00%> (-1.48%)	:arrow_down:
kgforge/specializations/resolvers/store_service.py	21.95% <0.00%> (+0.52%)	:arrow_up: