[clang-tidy] Remove enforcement of rule C.48 from cppcoreguidelines-prefer-member-init

[carlosgalvezp]

This functionality has been deprecated, moved to cppcoreguidelines-use-default-member-init, which is an alias of modernize-use-default-member-init. Remove the existing functionality in clang-tidy 19.

[llvmbot]

@llvm/issue-subscribers-clang-tidy