Build QGIS dependency as RelWithDebInfo

[Withalion]

fixes #4266

Introduce debug symbols for QGIS for better debugging of various QGIS issues.

P.S: This PR might look scary, but just the first commit is the necessary change, everything else is just a change in formatting.

[github-actions]

Pull Request Test Coverage Report for Build 20280785358

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 16 unchanged lines in 6 files lost coverage.
• Overall coverage increased (+0.09%) to 59.72%

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Files with Coverage Reduction	New Missed Lines	%
mm/app/map/inputcoordinatetransformer.cpp	1	0.0%
mm/app/position/providers/simulatedpositionprovider.cpp	1	90.91%
mm/app/projectwizard.cpp	1	2.12%
mm/app/autosynccontroller.cpp	3	51.43%
mm/app/identifykit.cpp	3	70.07%
mm/core/merginapi.cpp	7	75.39%

Totals
Change from base Build 20272619404:	0.09%
Covered Lines:	8626
Relevant Lines:	14444

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💛 - Coveralls

[github-actions]

📦 Build Artifacts Ready

OS	Status	Build	Info	Workflow run
macOS Build	📭	Build not yet complete or failed.
linux Build	📭	Build not yet complete or failed.
win64 Build	📬	Mergin Maps 53461 win64	Expires: 16/03/2026	#5346
Android Build	📭	Build not yet complete or failed.
iOS Build	📭	Build not yet complete or failed.