Merge #11490

11490: Correctly fix formatting doc tests with generics r=Veykril a=KarlWithK

Before the doc_test would be outputted like this:
```zsh
"Foo<T, U>::t"
```
However, this would cause problems with shell redirection. I've changed it
so when generics are involved we simply wrap the expression under quotes as so:
```zsh
"\"Foo<T, U>::t\""
```

Note:
At the cost of adding this, I had to allocate a new string via
`format!{}`. However, I argue this is alright as this for just for
outputting the name of the doc test.

The following tests have been changed:
```
runnables::tests::doc_test_type_params
runnables::tests::test_doc_runnables_impl_mod
runnables::tests::test_runnables_doc_test_in_impl
```

Closes  https://github.com/rust-analyzer/rust-analyzer/issues/11489

Co-authored-by: KarlWithK <jocelinc60@outlook.com>
Co-authored-by: SeniorMars <jocelinc60@outlook.com>