[clang] [libc++] Fixed uniform_real_distribution.h where it was allowing initialization with non floating point types (PR #70485)

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@@ -27,6 +28,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 template<class _RealType = double>
 class _LIBCPP_TEMPLATE_VIS uniform_real_distribution
 {
+     static_assert(std::is_floating_point<_RealType>::value, "result_type must be a floating point type");
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philnik777 wrote:

This needs a test. You can take a look at `libcxx/test/libcxx/input.output/iostream.format/input.streams/traits_mismatch.verify.cpp` for an example of how to check static assertions.

https://github.com/llvm/llvm-project/pull/70485