Fix Grpc graph fuzz test

Correct stream ids of semantic and pixel streams.
Bug: 168847367
Test: ran the fuzz test.

Change-Id: I163c692710bdbde541c279bbc9a1045ee400fa77
Merged-In: I163c692710bdbde541c279bbc9a1045ee400fa77
diff --git a/computepipe/tests/fuzz/GrpcGraphFuzzer.cpp b/computepipe/tests/fuzz/GrpcGraphFuzzer.cpp
index 338b3f8..0f93aac 100644
--- a/computepipe/tests/fuzz/GrpcGraphFuzzer.cpp
+++ b/computepipe/tests/fuzz/GrpcGraphFuzzer.cpp
@@ -139,12 +139,12 @@
             }
             case DISPATCH_PIXEL_DATA: {
                 runner::InputFrame inputFrame(0, 0, PixelFormat::RGB, 0, nullptr);
-                graph->dispatchPixelData(/*streamIndex =*/1, /*timestamp =*/0,
+                graph->dispatchPixelData(/*streamIndex =*/2, /*timestamp =*/0,
                                          /*inputFrame =*/inputFrame);
                 break;
             }
             case DISPATCH_SERIALIZED_DATA: {
-                graph->dispatchSerializedData(/*streamIndex =*/2, /* timestamp =*/0, /* data =*/"");
+                graph->dispatchSerializedData(/*streamIndex =*/1, /* timestamp =*/0, /* data =*/"");
                 break;
             }
             case DISPATCH_GRAPH_TERMINATION_MSG: {