test_onroad: skip more frames for ui timings

selfdrive/test/test_onroad.py

@@ -207,7 +207,7 @@ class TestOnroad:
     result += "------------------------------------------------\n"
 
     # skip first few frames -- connecting to vipc
-    ts = self.ts['uiDebug']['drawTimeMillis'][10:]
+    ts = self.ts['uiDebug']['drawTimeMillis'][15:]
     result += f"min  {min(ts):.2f}ms\n"
     result += f"max  {max(ts):.2f}ms\n"
     result += f"std  {np.std(ts):.2f}ms\n"