Update emscripten version

cmake/patches/sol2-3.3.0-clang-optional.patch

@@ -1,14 +1,14 @@
 --- a/include/sol/optional_implementation.hpp
 +++ b/include/sol/optional_implementation.hpp
-@@ -2189,7 +2189,10 @@
+@@ -2190,6 +2190,9 @@
  		template <class... Args>
  		T& emplace(Args&&... args) noexcept {
  			static_assert(std::is_constructible<T, Args&&...>::value, "T must be constructible with Args");
-
+-
++
  			*this = nullopt;
 -			this->construct(std::forward<Args>(args)...);
 +			// Reference specialization stores a pointer; set it directly.
 +			// construct() only exists in the non-reference specialization.
 +			m_value = std::addressof(std::forward<Args>(args)...);
-+			return *m_value;
- 		}
++			return *m_value;