Fixes: dotnet#7777

The last set of ignored test categories have been removed or migrated to
existing tests:

  * Test configurations related to AotMode=Hybrid and AotMode=Full have been removed.

  * BuildTest.CheckSequencePointGeneration has been removed due to it relying on mono symbol output.

  * EnvironmentContentTests.CheckBuildIdIsUnique has been removed due to it relying on mono symbol output.

  * PackagingTest.CheckManagedSymbolsArchive has been removed due to it relying on mono symbol output.

  * InstallAndRunTests.MonoSymbolicateAndroidStackTrace has been removed due to it relying on mono symbol output.

  * InstallAndRunTests.MonoSymbolicateNetStandardStackTrace has been removed due to it relying on mono symbol output.

  * EmbeddedDSOTests.BinariesExist removed as it is implicitly covered by tests that validate .apk contents.

  * EmbeddedDSOTests.EnvironmentFileContents removed as it is covered by BuildTest.CheckAssemblyCounts.

  * EmbeddedDSOTests.DSOPageAlignment assert moved to PackagingTest.EmbeddedDSOs.

  * EmbeddedDSOTests.DSOCompressionMode and EmbeddedDSOTests.AndroidManifestHasFlag removed as they are covered by PackagingTest.EmbeddedDSOs.