makepanda: Run correct interpreter when running --tests with 3.13t

makepanda/makepandacore.py

@@ -2126,6 +2126,10 @@ def SdkLocatePython(prefer_thirdparty_python=False):
         SDK["PYTHON"] = sdkdir
         SDK["PYTHONEXEC"] = SDK["PYTHON"] + "/python"
 
+        gil_disabled = locations.get_config_var("Py_GIL_DISABLED")
+        if gil_disabled and int(gil_disabled):
+            SDK["PYTHONEXEC"] += "3.13t"
+
         if (GetOptimize() <= 2):
             SDK["PYTHONEXEC"] += "_d.exe"
         else: