chore(deps): update dependency prettier to v1.16.1 (#2203)

This PR contains the following updates:

| Package | Type | Update | Change | References |
|---|---|---|---|---|
| prettier | devDependencies | minor | `1.15.3` -> `1.16.1` | [homepage](https://prettier.io), [source](https://togithub.com/prettier/prettier) |

---

### Release Notes

<details>
<summary>prettier/prettier</summary>

### [`v1.16.1`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#&#8203;1161)

[Compare Source](https://togithub.com/prettier/prettier/compare/1.16.0...1.16.1)

[diff](https://togithub.com/prettier/prettier/compare/1.16.0...1.16.1)

-   JavaScript: Do not format functions with arguments as react hooks ([#&#8203;5778] by [@&#8203;SimenB])

    The formatting added in Prettier 1.16 would format any function receiving an
    arrow function and an array literal to match React Hook's documentation.
    Prettier will now format this the same as before that change if the arrow
    function receives any arguments.

    <!-- prettier-ignore -->

    ```js
    // Input
    ["red", "white", "blue", "black", "hotpink", "rebeccapurple"].reduce(
      (allColors, color) => {
        return allColors.concat(color);
      },
      []
    );

    // Output (Prettier 1.16.0)
    ["red", "white", "blue", "black", "hotpink", "rebeccapurple"].reduce((
      allColors,
      color
    ) => {
      return allColors.concat(color);
    }, []);

    // Output (Prettier 1.16.1)
    ["red", "white", "blue", "black", "hotpink", "rebeccapurple"].reduce(
      (allColors, color) => {
        return allColors.concat(color);
      },
      []
    );
    ```

-   JavaScript: Add necessary parentheses for decorators ([#&#8203;5785] by [@&#8203;ikatyang])

    Parentheses for decorators with nested call expressions are optional for legacy decorators
    but they're required for decorators in the current [proposal](https://tc39.github.io/proposal-decorators/#sec-syntax).

    <!-- prettier-ignore -->

    ```js
    // Input
    class X {
      @&#8203;(computed().volatile())
      prop
    }

    // Output (Prettier 1.16.0)
    class X {
      @&#8203;computed().volatile()
      prop
    }

    // Output (Prettier 1.16.1)
    class X {
      @&#8203;(computed().volatile())
      prop
    }
    ```

-   TypeScript: Stable parentheses for function type in the return type of arrow function ([#&#8203;5790] by [@&#8203;ikatyang])

    There's a regression introduced in 1.16 that
    parentheses for function type in the return type of arrow function were kept adding/removing.
    Their parentheses are always printed now.

    <!-- prettier-ignore -->

    ```ts
    // Input
    const foo = (): (() => void) => (): void => null;
    const bar = (): () => void => (): void => null;

    // First Output (Prettier 1.16.0)
    const foo = (): () => void => (): void => null;
    const bar = (): (() => void) => (): void => null;

    // Second Output (Prettier 1.16.0)
    const foo = (): (() => void) => (): void => null;
    const bar = (): () => void => (): void => null;

    // Output (Prettier 1.16.1)
    const foo = (): (() => void) => (): void => null;
    const bar = (): (() => void) => (): void => null;
    ```

-   MDX: Correctly recognize inline JSX ([#&#8203;5783] by [@&#8203;ikatyang])

    Previously, some inline JSXs are wrongly recognized as block HTML/JSX,
    which causes unexpected behaviors. This issue is now fixed.

    <!-- prettier-ignore -->

    ```md
    <!-- Input -->
    _foo <InlineJSX /> bar_

    <!-- Output (Prettier 1.16.0) -->
    _foo

    <InlineJSX /> bar_

    <!-- Output (Prettier 1.16.1) -->
    _foo <InlineJSX /> bar_
    ```

[@&#8203;ikatyang]: https://togithub.com/ikatyang

[@&#8203;simenb]: https://togithub.com/SimenB

[#&#8203;5778]: https://togithub.com/prettier/prettier/pull/5778

[#&#8203;5783]: https://togithub.com/prettier/prettier/pull/5783

[#&#8203;5785]: https://togithub.com/prettier/prettier/pull/5785

[#&#8203;5790]: https://togithub.com/prettier/prettier/pull/5790

### [`v1.16.0`](https://togithub.com/prettier/prettier/blob/master/CHANGELOG.md#&#8203;1160)

[Compare Source](https://togithub.com/prettier/prettier/compare/1.15.3...1.16.0)

[diff](https://togithub.com/prettier/prettier/compare/1.15.3...1.16.0)

🔗 [Release Notes](https://prettier.io/blog/2019/01/20/1.16.0.html)

</details>

---

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---

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---

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package.json

@@ -115,7 +115,7 @@
     "mock-req": "0.2.0",
     "multer": "1.4.1",
     "node-fetch": "2.3.0",
-    "prettier": "1.15.3",
+    "prettier": "1.16.1",
     "prettier-check": "2.0.0",
     "qs-middleware": "1.0.3",
     "redis-mock": "0.42.0",

packages/apollo-server-core/src/utils/dispatcher.ts

@@ -30,7 +30,7 @@ export class Dispatcher<T> {
   public invokeDidStartHook<
     TMethodName extends FunctionPropertyNames<
       Required<T>,
-      ((...args: any[]) => AnyFunction | void)
+      (...args: any[]) => AnyFunction | void
     >,
     TEndHookArgs extends Args<ReturnType<AsFunction<T[TMethodName]>>>
   >(