Add segmentation data publisher to camera plugin

[dscroft]

Segmentation topic will appear for Camera nodes that have segmentation available. Data will only be published if subscribers are connected.

Description
Camera plugin does not have segmentation data available.

Related Issues
N/A

Affected Packages
List of affected packages:

• webots_ros2
• webots_ros2_driver

Tasks
NA

Additional context
NA

[lukicdarkoo]

@dscroft Thank you. I synced with the main branch and allowed CI.

It looks good. Could you please add a changelog. It would also be good to add a simple test.

[dscroft]

Test added

[lukicdarkoo]

@dscroft Thank you for the test. It seems there is a bug, can you take a look:

build/webots_ros2_tests/pytest.xml: 11 tests, 0 errors, 1 failure, 0 skipped
- webots_ros2_tests.test.test_system_driver test_system_driver
  <<< failure message
    test_system_driver.TestDriver.testSegmentation failed
  >>>

[dscroft]

Found the issue, pushed fix.