[midPoint-git] [Evolveum/midpoint] d52a98: Fix null-value "equals" filter in dummy resource

[mederly]

  Branch: refs/heads/master
  Home:   https://github.com/Evolveum/midpoint
  Commit: d52a98cdcba2f25e3e3b4f84d27a3272743a12da
      https://github.com/Evolveum/midpoint/commit/d52a98cdcba2f25e3e3b4f84d27a3272743a12da
  Author: Pavol Mederly <mederly at evolveum.com>
  Date:   2020-12-18 (Fri, 18 Dec 2020)

  Changed paths:
    M icf-connectors/dummy-connector/src/main/java/com/evolveum/icf/dummy/connector/AbstractObjectDummyConnector.java

  Log Message:
  -----------
  Fix null-value "equals" filter in dummy resource

Dummy connector was fixed to work correctly with null-valued
equals filters. However, the solution is still too brittle,
mainly because of the ConnId EqualFilter implementation:
the exact state (null vs. empty collection) in the filter must
be equal to the one in the connector object for them to be matched.

Relates to MID-1460.