fix: dns config name

[bschimke95]

The DNS config was not properly passed down to the update call which caused the DNS feature to always be disabled.

[github-actions]

Test coverage for 26c1bbb

coverage-report: install_deps /home/runner/work/k8s-operator/k8s-operator/charms/worker/k8s> python -I -m pip install 'coverage[toml]'
coverage-report: commands[0] /home/runner/work/k8s-operator/k8s-operator/charms/worker/k8s> coverage report
Name                                    Stmts   Miss  Cover
-----------------------------------------------------------
lib/charms/k8s/v0/k8sd_api_manager.py     279     29    90%
src/charm.py                              473    233    51%
src/cloud_integration.py                   80      3    96%
src/config/extra_args.py                   27      1    96%
src/containerd.py                         140     16    89%
src/cos_integration.py                     33     12    64%
src/events/update_status.py                48     10    79%
src/inspector.py                           40      4    90%
src/kube_control.py                        39     31    21%
src/literals.py                             1      0   100%
src/protocols.py                           16      3    81%
src/reschedule.py                          77      4    95%
src/snap.py                               165     10    94%
src/token_distributor.py                  181    109    40%
src/upgrade.py                             31      1    97%
-----------------------------------------------------------
TOTAL                                    1630    466    71%
coverage-report: OK (1.24=setup[1.03]+cmd[0.21] seconds)
congratulations :) (1.29 seconds)

Static code analysis report

Run started:2024-11-26 18:03:48.017425

Test results:
  No issues identified.

Code scanned:
  Total lines of code: 3536
  Total lines skipped (#nosec): 3
  Total potential issues skipped due to specifically being disabled (e.g., #nosec BXXX): 0

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):