Improve Flux combined maintainers list

[scottrigby]

Follow-up on #134

• PR to update CNCF project maintainers CSV
• Change formatting of each repo's MAINTAINERS file to an automatically ingestable format
  • Ensure important info like company and contact info is still accessible somehow from this file. Either a linked, separate file or add to metadata somehow that still allows machines to read these
  • Ensure alumni are also recorded in MAINTAINERS files, but should not be confused in combined file with current maintainers
• Automate the combined flux-project-maintainers.yaml file from those machine-readable MAINTAINERS files
  • warn on differences or failure

[dholbach]

@scottrigby Unfortunately there's yaml/yaml#48 so merging of sequences doesn't quite work like implemented in #134 - I tried writing a python script to generate some of the info, but it failed loading your YAML.

[dholbach]

To illustrate the problem:

community on  main [?] 
❯ python -c "import yaml; yaml.safe_load(open('project/flux-project-maintainers.yaml').read())"
Traceback (most recent call last):
  File "<string>", line 1, in <module>
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/__init__.py", line 125, in safe_load
    return load(stream, SafeLoader)
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/__init__.py", line 81, in load
    return loader.get_single_data()
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/constructor.py", line 51, in get_single_data
    return self.construct_document(node)
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/constructor.py", line 60, in construct_document
    for dummy in generator:
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/constructor.py", line 413, in construct_yaml_map
    value = self.construct_mapping(node)
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/constructor.py", line 217, in construct_mapping
    self.flatten_mapping(node)
  File "/home/daniel/.local/lib/python3.8/site-packages/yaml/constructor.py", line 194, in flatten_mapping
    raise ConstructorError("while constructing a mapping",
yaml.constructor.ConstructorError: while constructing a mapping
  in "<unicode string>", line 42, column 3:
    - <<: *flux2
      ^
expected a mapping for merging, but found scalar
  in "<unicode string>", line 13, column 3:
    - relu
      ^

community on  main [?] 
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