[CM] Fix controller missing update cycles in a real setup (backport #1774)

[mergify]

When we introduced supporting different update rates to the controllers. I realized that inside the tests I assumed a perfect system without any jitter and it was performing well.

ros2_control/controller_manager/test/test_controller_manager.cpp

Line 512 in ab84b74

time += rclcpp::Duration::from_seconds(0.01);

However, this is not the case in reality. We have some influence of system jitter, and due to the jitter if the system sleeps a bit less than what it should, then it skips and waits for the next cycle, and that's the reason we have double the period in most occasions.

ros2_control/controller_manager/test/test_controller_manager.cpp

Lines 502 to 504 in 3c985db

	rclcpp::Time old_time = time;
	cm_->get_clock()->sleep_until(old_time + PERIOD);
	time = cm_->get_clock()->now();

This PR introduces a new approach to solving this issue and the tests have been updated to be more realistic than earlier version

Fixes: #1769
Fixes: #1574

---

This is an automatic backport of pull request #1774 done by Mergify.

[mergify]

Cherry-pick of 814137d has failed:

On branch mergify/bp/iron/pr-1774
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Changes to be committed:
	modified:   controller_interface/include/controller_interface/controller_interface_base.hpp
	modified:   controller_manager/CMakeLists.txt
	modified:   controller_manager/include/controller_manager/controller_manager.hpp
	modified:   controller_manager/include/controller_manager/controller_spec.hpp

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   controller_manager/src/controller_manager.cpp
	both modified:   controller_manager/test/test_controller_manager.cpp

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[codecov]

Codecov Report

Attention: Patch coverage is 65.85366% with 14 lines in your changes missing coverage. Please review.

Project coverage is 62.32%. Comparing base (7797a38) to head (dd2a1f3).
Report is 1 commits behind head on iron.

Files with missing lines	Patch %	Lines
controller_manager/src/controller_manager.cpp	59.09%	8 Missing and 1 partial ⚠️
...ontroller_manager/test/test_controller_manager.cpp	70.58%	2 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             iron    #1858      +/-   ##
==========================================
- Coverage   62.32%   62.32%   -0.01%     
==========================================
  Files         112      112              
  Lines       13108    13137      +29     
  Branches     8891     8909      +18     
==========================================
+ Hits         8170     8187      +17     
- Misses        951      963      +12     
  Partials     3987     3987              

Flag	Coverage Δ
unittests	62.32% <65.85%> (-0.01%)	⬇️

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

Files with missing lines	Coverage Δ
...controller_interface/controller_interface_base.hpp	83.33% <ø> (ø)
.../include/controller_manager/controller_manager.hpp	41.02% <100.00%> (ø)
...r_manager/test/test_controller/test_controller.cpp	84.44% <100.00%> (+0.35%)	⬆️
...r_manager/test/test_controller/test_controller.hpp	100.00% <ø> (ø)
...ontroller_manager/test/test_controller_manager.cpp	55.67% <70.58%> (+1.02%)	⬆️
controller_manager/src/controller_manager.cpp	70.27% <59.09%> (-0.42%)	⬇️

... and 2 files with indirect coverage changes

[christophfroehlich]

LGTM. Binary build failure is because of missing sync of realtime_tools