(perf): Add a missing noexcept to a pytype constructor (#3236)

* Add a missing noexcept to pytypes constructor.

Adds a few missing noexcept to PyType constructors for perf reasons.

* Revert exception ctor

include/pybind11/pytypes.h

@@ -761,7 +761,7 @@ template <typename T>
 struct arrow_proxy {
     T value;
 
-    arrow_proxy(T &&value) : value(std::move(value)) { }
+    arrow_proxy(T &&value) noexcept : value(std::move(value)) { }
     T *operator->() const { return &value; }
 };