CVE-2023-49081

### Summary
Improper validation make it possible for an attacker to modify the HTTP request (e.g. to insert a new header) or even create a new HTTP request if the attacker controls the HTTP version.

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### Details
The vulnerability only occurs if the attacker can control the HTTP version of the request (including its type).
For example if an unvalidated JSON value is used as a version and the attacker is then able to pass an array as the `version` parameter.
Furthermore, the vulnerability only occurs when the `Connection` header is passed to the `headers` parameter.

At this point, the library will use the parsed value to create the request. If a list is passed, then it bypasses validation and it is possible to perform CRLF injection.

### PoC
The POC below shows an example of providing an unvalidated array as a version:
https://gist.github.com/jnovikov/184afb593d9c2114d77f508e0ccd508e

### Impact
CRLF injection leading to Request Smuggling.

### Workaround
If these specific conditions are met and you are unable to upgrade, then validate the user input to the `version` parameter to ensure it is a `str`.

Patch: https://github.com/aio-libs/aiohttp/pull/7835/files