CR: await promise -> return promise

@kentcdodds:
> Rather than `await promise`, I'd prefer `return promise`. Maybe I'm
being irrational here, but it feels better to me.

@sompylasar:
> I'm changing this, but if this line was the only one with `await`
expression, then `eslint` would say `async` function must have an
`await`. We are lucky that there are more `await`s in all the tests.
>
> P.S. I don't agree with this rule because `async` functions have
their use for the error handling; `async` function is just the one that
is wrapped in a `return new Promise(...)`.

Author: sompylasar

src/__tests__/wait-for-element.js

@@ -97,7 +97,7 @@ test('it waits for the callback to return a value and only reacts to DOM mutatio
   expect(container).toMatchSnapshot()
   expect(testEl.parentNode).toBe(container)
 
-  await promise
+  return promise
 })
 
 test('it waits for the next DOM mutation with default callback', async () => {
@@ -126,7 +126,7 @@ test('it waits for the next DOM mutation with default callback', async () => {
   expect(errorHandler).toHaveBeenCalledTimes(0)
   expect(document.body).toMatchSnapshot()
 
-  await promise
+  return promise
 })
 
 test('it waits for the attributes mutation if configured', async () => {
@@ -161,7 +161,7 @@ test('it waits for the attributes mutation if configured', async () => {
   expect(successHandler).toHaveBeenCalledWith('PASSED')
   expect(errorHandler).toHaveBeenCalledTimes(0)
 
-  await promise
+  return promise
 })
 
 test('it throws if timeout is exceeded', async () => {
@@ -197,7 +197,7 @@ test('it throws if timeout is exceeded', async () => {
   expect(errorHandler.mock.calls[0]).toMatchSnapshot()
   expect(container).toMatchSnapshot()
 
-  await promise
+  return promise
 })
 
 test('it throws the same error that the callback has thrown if timeout is exceeded', async () => {
@@ -233,7 +233,7 @@ test('it throws the same error that the callback has thrown if timeout is exceed
   expect(errorHandler.mock.calls[0]).toMatchSnapshot()
   expect(container).toMatchSnapshot()
 
-  await promise
+  return promise
 })
 
 test('it returns immediately if the callback returns the value before any mutations', async () => {
@@ -274,5 +274,5 @@ test('it returns immediately if the callback returns the value before any mutati
 
   expect(container).toMatchSnapshot()
 
-  await promise
+  return promise
 })