The existing way of verifying shared library dependencies, used for
System.Globalization.Native.so, doesn't work on platforms that don't
have ldd or where ldd doesn't support the -r option.
This change makes the check happen on non-Alpine Linux only for now.
It also refactors the way the check is performed. Instead of doing it
post build in the build.sh, it is now performed as a postbuild phase
of the System.Globalization.Native target and it is also generalized
so that we can easily add such verification to other build targets.

@jkotas can you take a look please?

@dotnet-bot test Windows_NT x64 Release Priority 1 Build and Test please