Svelte cleanup docs match React language

Author: kyle-n

docs/react-testing-library/api.mdx

@@ -289,10 +289,8 @@ expect(firstRender).toMatchDiffSnapshot(asFragment())
 
 Unmounts React trees that were mounted with [render](#render).
 
-> Please note that this is done automatically if the testing framework you're
-> using supports the `afterEach` global and it is injected to your testing
-> environment (like mocha, Jest, and Jasmine). If not, you will need to do
-> manual cleanups after each test.
+> This is called automatically if your testing framework (such as mocha, Jest or
+> Jasmine) injects a global `afterEach()` function into the testing environment.
 
 For example, if you're using the [ava](https://github.com/avajs/ava) testing
 framework, then you would need to use the `test.afterEach` hook like so:

docs/svelte-testing-library/api.mdx

@@ -70,8 +70,8 @@ const {results} = render(YourComponent, {myProp: 'value'})
 
 ## `cleanup`
 
-> You don't need to import or use this, it's done automagically for you with
-> `globals: true` in your test config!
+> This is called automatically if your testing framework (such as mocha, Jest or
+> Jasmine) injects a global `afterEach()` function into the testing environment.
 
 Unmounts the component from the container and destroys the container.