Add ppa for proposed kernel release

[yhaliaw]

Applicable spec: NA

Overview

Use the proposed kernel version for the juju machine hosting the application

Rationale

Suggested by the kernel team to address stability issues.

Checklist

• The charm style guide was applied
• The contributing guide was applied
• The changes are compliant with ISD054 - Managing Charm Complexity
• The documentation is generated using src-docs
• The documentation for charmhub is updated.
• The PR is tagged with appropriate label (urgent, trivial, complex)

src-docs for this repo is being worked on in a different PR.

[github-actions]

Test coverage for a5ea525

Name                                    Stmts   Miss Branch BrPart  Cover   Missing
-----------------------------------------------------------------------------------
src/charm.py                              397     84     96     24    76%   123-125, 185-193, 205-209, 278->282, 303-308, 318, 332-333, 342-360, 381-383, 394-397, 404, 407-408, 422, 429, 448->454, 454->465, 487-488, 492-493, 508-509, 511-512, 546-554, 565-566, 581-582, 594-596, 599->exit, 603-605, 637-638, 640-641, 643-644, 717->719, 779-780, 796, 809
src/errors.py                              22      0      0      0   100%
src/event_timer.py                         42      8      4      0    74%   94-97, 117-120
src/firewall.py                            43     25     10      0    38%   38-42, 64-67, 75-149
src/github_type.py                         36      0      0      0   100%
src/lxd_type.py                            38      0      2      0   100%
src/repo_policy_compliance_service.py       5      5      0      0     0%   4-14
src/runner.py                             255     29     74     21    84%   40->44, 188-195, 201-207, 266-271, 276, 296, 345->348, 351-353, 360, 374, 384, 388, 390, 405, 449-454, 464, 553, 588, 614, 619-631, 645, 665
src/runner_manager.py                     221     26     88      9    87%   155, 212-214, 227-228, 240-242, 248-253, 257-258, 268-269, 285, 340, 365-369, 388, 406, 549, 569
src/runner_type.py                         52      0     12      0   100%
src/utilities.py                           68      6     20      8    84%   74->76, 78->84, 89-91, 119, 132, 167, 220
-----------------------------------------------------------------------------------
TOTAL                                    1179    183    306     62    81%

Static code analysis report

Run started:2023-08-22 03:00:12.037972

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 2659
  Total lines skipped (#nosec): 0
  Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 9

Run metrics:
  Total issues (by severity):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
  Total issues (by confidence):
  	Undefined: 0
  	Low: 0
  	Medium: 0
  	High: 0
Files skipped (0):