Latched map subscriber QoS depth 1

[doisyg]

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Basic Info

Info	Please fill out this column
Ticket(s) this addresses	(add tickets here #1)
Primary OS tested on	Ubuntu
Robotic platform tested on	Deoxry robot
Does this PR contain AI generated software?	No
Was this PR description generated by AI software?	No

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Description of contribution in a few bullet points

Change the depth of the map and costmap related subscribers from 10 (default) to 1 (explicitly through the constructor nav2::qos::LatchedSubscriptionQoS(1)). This matches the depth of the latched publishers (default depth of 1).
This is needed for us in the context of using huge maps + Zenoh SHM in order to not have to set ZENOH_SHM_ALLOC_SIZE to the size of the message * [10 (the depth of the subscriber) + 2 (recommended margin)] and optimizing RAM usage.
This works well for our setup (all comms are local). Though a point to discuss is if this could cause issues for receiving map/costmap over wireless / lossy connections. But since we are only touching latched topics (and matching the publishers), I am not sure it is really an issue.
An alternative would be to have the user override the QoS of these subscribers.

(side change: use nav2::qos for test_map_saver_cli and test_map_saver_publisher)

Description of documentation updates required from your changes

Description of how this change was tested

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Future work that may be required in bullet points

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
• Should this be backported to current distributions? If so, tag with backport-*.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

Files with missing lines	Coverage Δ
nav2_amcl/src/amcl_node.cpp	86.37% <100.00%> (ø)
..._2d/include/nav2_costmap_2d/costmap_subscriber.hpp	100.00% <100.00%> (ø)
...stmap_2d/plugins/costmap_filters/binary_filter.cpp	94.66% <100.00%> (ø)
...tmap_2d/plugins/costmap_filters/keepout_filter.cpp	78.83% <100.00%> (ø)
...ostmap_2d/plugins/costmap_filters/speed_filter.cpp	95.12% <100.00%> (ø)
nav2_costmap_2d/plugins/static_layer.cpp	74.31% <100.00%> (ø)
nav2_costmap_2d/plugins/voxel_layer.cpp	94.73% <100.00%> (ø)
nav2_map_server/src/map_saver/map_saver.cpp	94.93% <100.00%> (ø)

... and 9 files with indirect coverage changes

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