makepanda: Look for the macOS 13.1 SDK

[skip ci]

makepanda/makepandacore.py

@@ -2443,7 +2443,7 @@ def SdkLocateMacOSX(archs = []):
         # Prefer pre-10.14 for now so that we can keep building FMOD.
         sdk_versions += ["10.13", "10.12", "10.11", "10.10", "10.9"]
 
-    sdk_versions += ["13.0", "12.3", "11.3", "11.1", "11.0"]
+    sdk_versions += ["13.1", "13.0", "12.3", "11.3", "11.1", "11.0"]
 
     if 'arm64' not in archs:
         sdk_versions += ["10.15", "10.14"]