[controller_server] [FollowPath] Allow multiple progress checkers

[doisyg]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses
Primary OS tested on	Ubuntu
Robotic platform tested on	Dexory sim

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Description of contribution in a few bullet points

The parameters goal_checker_plugins and controller_plugins are list of strings, allowing multiple plugin configuration, whereas progress_checker_plugin is a single string allowing the declaration of only one goal checker.

This PR initializes the progress checker plugin(s) in the same way as for the goal checker and controller plugins: it is now a list of string and was renamed from progress_checker_plugin to progress_checker_plugins. This allows the initialization of multiple goal checker that can be chosen from the added progress_checker_id field of the FollowPath action

This is a breaking change as the configuration yaml has to be updated from

 controller_server:
   ros__parameters:
     progress_checker_plugin: "progress_checker"

to

 controller_server:
   ros__parameters:
     progress_checker_plugins: ["progress_checker"]

Description of documentation updates required from your changes

• Name of parameter and default configuration in all examples
• Migration guide

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Future work that may be required in bullet points

For Maintainers:

• Check that any new parameters added are updated in navigation.ros.org
• Check that any significant change is added to the migration guide
• Check that any new features OR changes to existing behaviors are reflected in the tuning guide
• Check that any new functions have Doxygen added
• Check that any new features have test coverage
• Check that any new plugins is added to the plugins page
• If BT Node, Additionally: add to BT's XML index of nodes for groot, BT package's readme table, and BT library lists

[SteveMacenski]

I generally approve, but I want to see the docs PR to match since there will be a bunch of places these new ports and vectorized plugins need to be set. Last time we did this, there were vestiges in docs of it for way too long causing problems with copy+pasting of YAML

Edit: I lied. See below.

[mergify]

@doisyg, your PR has failed to build. Please check CI outputs and resolve issues.
You may need to rebase or pull in main due to API changes (or your contribution genuinely fails).

[SteveMacenski]

Just waiting on CI