Fix SSLCipherList typing error in IMAP coordinator

[vexofp]

Proposed change

This PR was split off from #105348 based on @bdraco 's feedback. It should be merged first, as without it the other will cause a mypy linting failure.

In imap/coordinator.py, a user-supplied string is currently being passed to client_context(), which is declared to actually take an instance of the SSLCipherList enumeration. This PR simply adds the necessary call to convert the string into such.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Deprecation (breaking change to happen in the future)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue:
• This PR is related to issue: Duplicate default SSLContext instances #105115
• Link to documentation pull request:

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[home-assistant]

Hey there @jbouwh, mind taking a look at this pull request as it has been labeled with an integration (imap) you are listed as a code owner for? Thanks!

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