[mono][ios] Add a functional test for testing SIGSEGV signal chaining to default handler on iOS platforms

[ivanpovazan]

Description

We should add a functional test which would verify that the SIGSEGV signal chaining to default handler works correctly on iOS platforms and that a crash report is properly generated when such signal is raised from native code.

The behavior got fixed in: #110741 and only manually verified with .NET MAUI iOS/MacCatalyst application.
However, we should improve our test coverage and catch any potential future regression early on.

[dotnet-policy-service]

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