build: Fix building for spice2x-20230929

> resolve third party libraries not building
> force include stdint.h in place of cstdint missing from windows.h now
> to be reverted after updates to spice2x master

external/discord-rpc/.clang-format

@@ -45,7 +45,6 @@ IncludeCategories:
   - Regex: '.*'
     Priority: 3
 IncludeIsMainRegex: '(_test|_win|_linux|_mac|_ios|_osx|_null)?$'
-IndentCaseLabels: false
 IndentWidth: 4
 IndentWrappedFunctionNames: false
 KeepEmptyLinesAtTheStartOfBlocks: false

external/rapidjson/document.h

@@ -323,8 +323,6 @@ struct GenericStringRef {
 
     GenericStringRef(const GenericStringRef& rhs) : s(rhs.s), length(rhs.length) {}
 
-    GenericStringRef& operator=(const GenericStringRef& rhs) { s = rhs.s; length = rhs.length; }
-
     //! implicit conversion to plain CharType pointer
     operator const Ch *() const { return s; }