Use AsyncAdaptedQueuePool in aiosqlite

Use AsyncAdaptedQueuePool in aiosqlite

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### Description
Change default pool in `aiosqlite` from `NullPool` to `AsyncAdaptedQueuePool`.
This ensures consistency with pysqlite and least surprise when migrating from sync to async.
See discussion in https://github.com/sqlalchemy/sqlalchemy/discussions/12285
Non regression tested by existing tests.

### Checklist
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This pull request is:

- [ ] A documentation / typographical / small typing error fix
	- Good to go, no issue or tests are needed
- [x] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #12291
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/12291
Pull-request-sha: 5a0872b8d431a6937eaf05fb132578aed5723b6a

Change-Id: I96b4d0b5154b34cd26d3ad89774229b0f5d8686f