test(fix): guard mpmlist with R2025a release check

Author: mfacchinelli

tests/system/package/tToolbox.m

@@ -16,7 +16,12 @@ function useMATLABR2025aOrAbove(testCase)
         end
 
         function checkMATLABPackage(testCase)
-            testCase.assumeEmpty(mpmlist(mag.buildtool.task.PackageTask.ToolboxName), "MAG Data Visualization installed as a MATLAB package.");
+
+            % MATLAB will still execute this method, even if the above
+            % check fails.
+            if ~isMATLABReleaseOlderThan("R2025a")
+                testCase.assumeEmpty(mpmlist(mag.buildtool.task.PackageTask.ToolboxName), "MAG Data Visualization installed as a MATLAB package.");
+            end
         end
     end