We could probably use parameterized tests for this to save some code.

Originally posted by @destogl in #461 (comment)

Description:

• File: controller_manager/test/test_controller_manager.cpp
• each test where controller switching is done has to be done also with BEST_EFFORT - this means that the test will have to be duplicated (we can optimize/reduce code in the second step)
• one example line with STRICT controller switch is here
• BEST_EFFORT means the following: if we have a situation where multiple controllers "are switched" and can not be switched the all other that can will be still switched
• this feature is not documented very well - please also add documentation into controller_manager/doc/userdoc.rst