Assert the refusal log with getMessage so the compat tests pass

[potiuk]

main is currently red on the provider compat jobs. The refusal-logging
assertions in the Amazon secrets tests read record.msg directly, and how a
record carries its payload depends on the Airflow version:

# main — structlog renders the format args before the stdlib record exists
LogRecord(msg="Connection id 'prod--x' contains '--'", args=())
    "prod--x" in r.msg          -> True

# the versions the compat jobs run against — plain stdlib logging
LogRecord(msg="%s id %r contains %r", args=("Connection", "prod--x", "--"))
    "prod--x" in r.msg          -> False        <- the failure
    "prod--x" in r.getMessage() -> True

So the assertions pass on main and fail under Compat 2.11.1:P3.10 and
Compat 3.0.6:P3.10:

assert 0 == 1
  where 0 = sum(refused_id in r.msg for r in refusals)

getMessage() renders in both shapes. The assertion still targets the refused
id rather than the wording, which was the point of moving off the rendered
sentence in the first place — that intent is unchanged, only the accessor.

This is a regression from #70878, where I moved these assertions off
getMessage() while addressing review feedback and verified only against main.
Compat runs on provider PRs, so it surfaced on the next provider PR rather than
on the one that introduced it.

Kept separate from #70899 (the Azure get_config follow-up) so the repair to
main can land on its own.

Test plan

• providers/amazon/tests/unit/amazon/aws/secrets/ — 73 passed locally
• Both record shapes checked directly: r.msg matches only the pre-rendered
  one, getMessage() matches both
• Test-only change; no production code touched
• ruff format clean

Was generative AI tooling used to co-author this PR?

• Yes — Claude Opus 5 (1M context)

Generated-by: Claude Opus 5 (1M context) following the guidelines at
https://github.com/apache/airflow/blob/main/contributing-docs/05_pull_requests.rst#gen-ai-assisted-contributions

[henry3260]

Thank you!

[github-actions]

Backport failed to create: v3-3-test. View the failure log Run details

Note: As of Merging PRs targeted for Airflow 3.X
the committer who merges the PR is responsible for backporting the PRs that are bug fixes (generally speaking) to the maintenance branches.

In matter of doubt please ask in #release-management Slack channel.

Status	Branch	Result
❌	v3-3-test

You can attempt to backport this manually by running:

cherry_picker 8146228 v3-3-test

This should apply the commit to the v3-3-test branch and leave the commit in conflict state marking
the files that need manual conflict resolution.

After you have resolved the conflicts, you can continue the backport process by running:

cherry_picker --continue

If you don't have cherry-picker installed, see the installation guide.