Behavior tree node for extracting pose from path (backport #4518)

[mergify]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses	open-navigation/opennav_coverage#64 #4516
Does this PR contain AI generated software?	(No)

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Description of contribution in a few bullet points

• Added behavior tree node that extracts a pose from a path at a specific index

Description of documentation updates required from your changes

• Need to document this behavior tree node

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For Maintainers:

• Check that any new parameters added are updated in docs.nav2.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

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This is an automatic backport of pull request #4518 done by [Mergify](https://mergify.com).

[mergify]

@mergify[bot], all pull requests must be targeted towards the main development branch.
Once merged into main, it is possible to backport to @iron, but it must be in main
to have these changes reflected into new distributions.