test: bump downstream MTK compat

AayushSabharwal · AayushSabharwal · commit 521688915271 · 2025-02-15T18:05:41.000+05:30
diff --git a/test/downstream/Project.toml b/test/downstream/Project.toml
@@ -34,7 +34,7 @@ DelayDiffEq = "5"
 DiffEqCallbacks = "3, 4"
 ForwardDiff = "0.10"
 JumpProcesses = "9.10"
-ModelingToolkit = "9.56"
+ModelingToolkit = "9.63"
 ModelingToolkitStandardLibrary = "2.7"
 NonlinearSolve = "2, 3, 4"
 Optimization = "4"
