Maintenance command for setting maintenance mode

[valyo]

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Add commands dds maintenance on and dds maintenance off for turning Maintenance mode on and off
works with ScilifelabDataCentre/dds_web#1286

• Add a summary of the changes and the related issue
• Add motivation and context regarding why the change is needed
• Fixes DDS-1348

Type of change

• New feature (non-breaking)

Checklist:

General

• I have added a row in the changelog
• Code change
  • Self-review of code done
  • Comments added, particularly in hard-to-understand areas

Repository / Releases

• Blocking PRs have been merged
• Rebase / update of branch done

Checks

• Formatting: Black & Prettier checks pass
• CodeQL passes
• Tests
  • The tests pass

[codecov]

Codecov Report

Merging #535 (110e68f) into dev (b9ad4f7) will increase coverage by 0.18%.
The diff coverage is 60.00%.

@@            Coverage Diff             @@
##              dev     #535      +/-   ##
==========================================
+ Coverage   41.92%   42.10%   +0.18%     
==========================================
  Files          29       30       +1     
  Lines        2645     2674      +29     
==========================================
+ Hits         1109     1126      +17     
- Misses       1536     1548      +12     

Impacted Files	Coverage Δ
dds_cli/__main__.py	41.87% <45.45%> (+0.06%)	⬆️
dds_cli/maintenance_manager.py	64.70% <64.70%> (ø)
dds_cli/__init__.py	91.25% <100.00%> (+0.11%)	⬆️

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[i-oden]

I like the "dds maintenance on/off" command. My suggestion regards reducing some code duplication, otherwise it'll work the exact same way