message: Update counter test to use MockComponentRuntime
diff: import assert from "assert";
  import { ISharedObjectFactory } from "@fluidframework/shared-object-base";
  -import { MockRuntime } from "@fluidframework/test-runtime-utils";
  +import { MockComponentRuntime } from "@fluidframework/test-runtime-utils";
  import { ISharedCounter, SharedCounter } from "..";
  describe("Counter", () => {
  @@ -17,7 +17,7 @@ describe("Counter", () => {
  });
  it("Can create a counter with default value", () => {
  - const testCounter = factory.create(new MockRuntime(), "counter") as ISharedCounter;
  + const testCounter = factory.create(new MockComponentRuntime(), "counter") as ISharedCounter;
  assert.ok(testCounter);
  assert.equal(testCounter.value, 0);
  });
  @@ -28,7 +28,7 @@ describe("Counter", () => {
  beforeEach(async () => {
  factory = SharedCounter.getFactory();
  - testCounter = factory.create(new MockRuntime(), "counter") as ISharedCounter;
  + testCounter = factory.create(new MockComponentRuntime(), "counter") as ISharedCounter;
  assert.ok(testCounter);
  });
  