test(mysql): provide concrete DBAPI connection attributes in mocks

[rite7sh]

Description

This PR updates the MySQL instrumentation integration tests to provide concrete DBAPI connection attributes (host, port, database) in mocked connection and cursor objects.
Previously, several tests emitted OpenTelemetry warnings due to MagicMock values being used for attributes such as db.name, net.peer.name, and net.peer.port. These warnings were noisy but did not cause test failures.
By setting realistic primitive values in the mocks, the tests now run without attribute type warnings, improving signal-to-noise ratio while keeping behavior unchanged.

Fixes #4114

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Ran MySQL instrumentation integration tests locally: tox -e py310-test-instrumentation-mysql-1

Does This PR Require a Core Repo Change?

• Yes. - Link to PR:
• No.

Checklist:

See contributing.md for styleguide, changelog guidelines, and more.

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated

[rite7sh]

This PR only updates tests and does not change runtime behavior or public APIs.
I guess no changelog entry is required. Could a maintainer please add the 'no changelog required' label if you agree?
Thank you :)

[xrmx]

Since some of this code is open coded in the tests, maybe create an helper and use it there and in the tests that requires it?

[rite7sh]

@xrmx gotcha I’ve updated the helper to pass attributes directly via MagicMock() and refactored the repeated setup into a small reusable helper to avoid duplication across tests.
Let me know if you'd prefer a different structure or naming here.

[xrmx]

I meant to call this helper in the tests where you are adding the very same thing but open coded. If you can't do that then try to split this helper in smaller pieces you can reuse in the tests.

[rite7sh]

@xrmx Yep, I went with the helper approach you suggested - refactored the repeated MagicMock setup into a shared make_mysql_commenter_mocks helper and updated all SQL commenter tests to use it.
This cleans up a lot of duplication . Let me know if you'd like anything changed or tweaked