Fix: export libraries and plugins from opennav_docking

[jcarlosgm30]

The current implementation exports neither the plugins nor the pose_filter library for use by projects outside opennav_docking.

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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	Gazebo simulation
Does this PR contain AI generated software?	No

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Description of contribution in a few bullet points

• Export pose_filter library and plugins.xml from opennav_docking to be used by external projects.

Description of documentation updates required from your changes

Nothing

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Future work that may be required in bullet points

Nothing

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