Remove useless function calls

[51-code]

Description

Coverity flagged this line in an equality test for ImmutableMap.java:

immutableMap1.map();

It is marked as useless because the return value is not utilized. The reason for the function call is to check for any side effects from calling it, to ensure immutability in the equality test.

However, equalsverifier is used in the project anyways, so the test is obsolete and can be removed to get rid of the Coverity defect.