[LifecycleNode] add bond_heartbeat_period

[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 Robot
Does this PR contain AI generated software?	No

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Description of contribution in a few bullet points

This PR adds the parameter bond_heartbeat_period to the lifecycle nodes.

The bond heart beat period of the lifecycle node was fixed to 0.1 (s). This PR doesn't change the default value but allows to customize it, and to disable the bond mechanism if <= 0.0 (so no pub/sub on /bond)

Description of documentation updates required from your changes

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Future work that may be required in bullet points

• Should we change the default to a longer period (i.e. less CPU usage on /bond subscribers) ?
• Should we also expose bond_heartbeat_timeout for setHeartbeatTimeout ? (I personally don't have an use case for this)

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

[doisyg]

https://github.com/ros-navigation/docs.nav2.org/pull/556

[SteveMacenski]

Just waiting on CI. I don't expect any issues, but since this touches every server, I want to make sure