Add another warning-as-error exception

Caused by a spatial audio header file.

Author: bmatherly

CMakeLists.txt

@@ -156,6 +156,9 @@ if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_BUILD_TYPE STREQUAL "Debug")
   # The following showed up in GCC 14, which I am using via msys2 on Windows.
   # Remove the following when Glaxnimate is fixed.
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-c++20-compat -Wno-dangling-reference")
+  # The following showed up in GCC 13.3.
+  # Remove the following when spatialaudio is fixed.
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-overloaded-virtual")
 endif ()
 
 if(MSVC)