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

[via llvm-commits]

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@@ -14,6 +14,7 @@
 #include <__random/is_valid.h>
 #include <iosfwd>
 #include <limits>
+#include <type_traits>
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philnik777 wrote:

Please include `<__type_traits/is_floating_point.h>` instead.

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