Backport test fix to garden

[scpeters]

🦟 Bug fix

Backports test fix in 409d8c5 from #2175 to garden

Summary

fix INTEGRATION_save_world's SdfGeneratorFixture.ModelWithNestedIncludes test

https://build.osrfoundation.org/view/ign-garden/job/ignition_gazebo-ci-gz-sim7-homebrew-amd64/145/

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov]

Codecov Report

Merging #2197 (505082c) into gz-sim7 (b0ddc34) will decrease coverage by 0.28%.
Report is 68 commits behind head on gz-sim7.
The diff coverage is 53.52%.

❗ Current head 505082c differs from pull request most recent head 6209149. Consider uploading reports for the commit 6209149 to get more accurate results

@@             Coverage Diff             @@
##           gz-sim7    #2197      +/-   ##
===========================================
- Coverage    65.01%   64.74%   -0.28%     
===========================================
  Files          353      357       +4     
  Lines        28618    29122     +504     
===========================================
+ Hits         18606    18854     +248     
- Misses       10012    10268     +256     

Files	Coverage Δ
include/gz/sim/EntityComponentManager.hh	100.00% <ø> (ø)
include/gz/sim/Link.hh	100.00% <ø> (ø)
include/gz/sim/Server.hh	100.00% <ø> (ø)
include/gz/sim/Util.hh	100.00% <ø> (ø)
src/Link.cc	95.09% <100.00%> (+0.32%)	⬆️
src/ServerConfig.cc	83.22% <100.00%> (+0.07%)	⬆️
src/SimulationRunner.cc	90.73% <100.00%> (-0.91%)	⬇️
src/SystemLoader.cc	62.59% <100.00%> (ø)
src/TestFixture.cc	100.00% <100.00%> (ø)
src/gui/QuickStartHandler.cc	82.35% <100.00%> (+1.10%)	⬆️
... and 35 more

... and 1 file with indirect coverage changes