service: change stop interface (#7816)

internal/mempool/reactor_test.go

@@ -96,7 +96,7 @@ func setupReactors(ctx context.Context, t *testing.T, numNodes int, chBuf uint)
 	t.Cleanup(func() {
 		for nodeID := range rts.reactors {
 			if rts.reactors[nodeID].IsRunning() {
-				require.NoError(t, rts.reactors[nodeID].Stop())
+				rts.reactors[nodeID].Stop()
 				rts.reactors[nodeID].Wait()
 				require.False(t, rts.reactors[nodeID].IsRunning())
 			}
@@ -184,8 +184,7 @@ func TestReactorBroadcastDoesNotPanic(t *testing.T) {
 		}()
 	}
 
-	err := primaryReactor.Stop()
-	require.NoError(t, err)
+	primaryReactor.Stop()
 	wg.Wait()
 }