removed the deep copy for the costmap_raw_ data using memcpy in prepareCostmap under costmap_2d_publisher.cpp (backport #4919)

[mergify]

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Basic Info

Info
Ticket(s) this addresses	#4914
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

• I modified the loop that was being used to copy raw costmap by using a memcpy instead

Description of documentation updates required from your changes

• None would be required as it is just an enhancement

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Future work that may be required in bullet points

• Further profiling costmap related functionalities to identify which processes are costing us the most.

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 #4919 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 @jazzy, but it must be in main
to have these changes reflected into new distributions.