Use default kernel instead of HWE kernel

[weiiwang01]

Applicable spec:

Overview

Use the default kernel instead of the HWE kernel in GitHub runner images. The current HWE kernel is causing some problems with LXD/Juju because of changes in AppArmor.

Rationale

We have a user complaining that the current GitHub runner’s use of the HWE kernel is causing problems in the GitHub workflow.

Juju Events Changes

Module Changes

Library Changes

Checklist

• The charm style guide was applied
• The contributing guide was applied
• The changes are compliant with ISD054 - Managing Charm Complexity
• The documentation for charmhub is updated.
• The PR is tagged with appropriate label (urgent, trivial, senior-review-required, documentation)
• The docs/changelog.md is updated with user-relevant changes in the format of keep a changelog v1.1.0
• The application version is incremented in app/pyproject.toml

[cbartz]

LGTM - but need internal decision if we want to proceed that way