Remove workaround for old Visual C++ bug

[kennykerr]

cppwinrt/cppwinrt/code_writers.h

Lines 1202 to 1208 in 8484e43

	//
	// Note: this use of a lambda is a workaround for a Visual C++ compiler bug:
	// https://developercommunity.visualstudio.com/content/problem/554130/incorrect-code-gen-when-invoking-a-conversion-oper.html
	// Once fixed, revert the function body back to this:
	//
	// return static_cast<% const&>(*this).%(%);
	//