Don't try to build FunctionalTests test assets as tests

[lambdageek]

They are just assemblies that can be referenced by other tests, not standalone tests, themselves.

Follow-up to #80391 to address apparent failures on the Android runtime-extra-platforms legs

[lambdageek]

/azp run runtime-extra-platforms

[ghost]

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Issue Details

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They are just assemblies that can be referenced by other tests, not standalone tests, themselves.

Author:	lambdageek
Assignees:	lambdageek
Labels:	area-Infrastructure-libraries
Milestone:	-

[lambdageek]

cc @simonrozsival

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[lambdageek]

@simonrozsival Well this didn't work.

I'm now suspecting src/tests/build.proj. In particular AllRunnableTestPaths which eventually goes into BuildAllAndroidApp which might be building everything as an APK?? Although I haven't figured out exactly what gets into AllRunnableTestPaths, yet.

runtime/src/tests/build.proj

Lines 258 to 264 in 8300e38

	<Target Name="BuildAllAndroidApp" DependsOnTargets="GetListOfTestCmds;FindCmdDirectories">
	<MSBuild
	Projects="$(MSBuildProjectFile)"
	Targets="BuildAndroidApp"
	Properties="_CMDDIR=%(TestDirectories.Identity)"
	Condition="'@(TestDirectories)' != ''" />
	</Target>

[lambdageek]

Closing in favor of #80909