Multithread improvements (backport #205)

[mergify]

This is an automatic backport of pull request #205 done by Mergify.
Cherry-pick of 5de3d76 has failed:

On branch mergify/bp/foxy/pr-205
Your branch is up to date with 'origin/foxy'.

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Changes to be committed:
	modified:   rmw_microxrcedds_c/include/rmw_microros/ping.h
	modified:   rmw_microxrcedds_c/src/callbacks.c
	modified:   rmw_microxrcedds_c/src/rmw_init.c
	modified:   rmw_microxrcedds_c/src/rmw_microros/ping.c
	modified:   rmw_microxrcedds_c/src/rmw_microros_internal/memory.h
	modified:   rmw_microxrcedds_c/src/rmw_microros_internal/types.h
	modified:   rmw_microxrcedds_c/src/rmw_request.c
	modified:   rmw_microxrcedds_c/src/rmw_response.c
	modified:   rmw_microxrcedds_c/src/rmw_take.c
	modified:   rmw_microxrcedds_c/src/rmw_wait.c
	modified:   rmw_microxrcedds_c/src/types.c

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   .github/workflows/ci.yml

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/github/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

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[github-actions]

Static memory analysis

Default configuration

MTU: 512 B
Input buffer size: 2048 B
Input history: 4
Output buffer size: 2048 B
Output history: 4

Entity	Qty	Size per unit
Context	2	5616 B
Topic	8	56 B
Service	4	248 B
Client	4	248 B
Subscription	4	272 B
Publisher	4	280 B
Node	4	208 B
Static input buffer	8	2136 B
Init options	6	64 B
Wait sets	4	56 B
Guard Condition	4	64 B

TOTAL: 34436 B

[codecov-commenter]

Codecov Report

Merging #206 (a5c0114) into foxy (1155805) will increase coverage by 0.02%.
The diff coverage is 93.75%.

@@            Coverage Diff             @@
##             foxy     #206      +/-   ##
==========================================
+ Coverage   47.85%   47.88%   +0.02%     
==========================================
  Files          40       40              
  Lines        1678     1675       -3     
  Branches      333      333              
==========================================
- Hits          803      802       -1     
+ Misses        665      662       -3     
- Partials      210      211       +1     

Impacted Files	Coverage Δ
rmw_microxrcedds_c/src/rmw_init.c	58.78% <ø> (ø)
rmw_microxrcedds_c/src/rmw_request.c	69.81% <ø> (ø)
rmw_microxrcedds_c/src/rmw_response.c	69.23% <ø> (ø)
rmw_microxrcedds_c/src/rmw_take.c	26.00% <ø> (ø)
rmw_microxrcedds_c/src/rmw_wait.c	73.01% <ø> (ø)
rmw_microxrcedds_c/src/types.c	64.66% <ø> (ø)
rmw_microxrcedds_c/src/rmw_microros/ping.c	45.45% <50.00%> (-4.55%)	⬇️
rmw_microxrcedds_c/src/callbacks.c	67.21% <100.00%> (+3.15%)	⬆️

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