migrate to ruamel.yaml.

[anarkiwi]

No description provided.

[codecov]

Codecov Report

Merging #3977 (85d9eb3) into master (1974945) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 85d9eb3 differs from pull request most recent head d738e9b. Consider uploading reports for the commit d738e9b to get more accurate results

@@            Coverage Diff             @@
##           master    #3977      +/-   ##
==========================================
+ Coverage   92.46%   92.49%   +0.03%     
==========================================
  Files          47       47              
  Lines        8872     8865       -7     
==========================================
- Hits         8203     8199       -4     
+ Misses        669      666       -3     

Impacted Files	Coverage Δ
faucet/config_parser_util.py	91.82% <100.00%> (+2.07%)	⬆️

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[gizmoguy]

deb packages for ruamel have been built: https://gitlab.com/faucetsdn/python3-ruamel-yaml/-/pipelines/415067921