[`flake8-bugbear`] Make `B911` example error out-of-the-box (#19051)
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## Summary
<!-- What's the purpose of the change? What does it do, and why? -->
Part of #18972
This PR makes [batched-without-explicit-strict
(B911)](https://docs.astral.sh/ruff/rules/batched-without-explicit-strict/#batched-without-explicit-strict-b911)'s
example error out-of-the-box
[Old example](https://play.ruff.rs/a897d96b-0749-4291-8a62-dfd4caf290a0)
```py
itertools.batched(iterable, n)
```
[New example](https://play.ruff.rs/1c1e0ab7-014c-4dc2-abed-c2cb6cd01f70)
```py
import itertools
itertools.batched(iterable, n)
```
Imports were also added to the "use instead" sections
## Test Plan
<!-- How was it tested? -->
N/A, no functionality/tests affected