#60283 yamllint

What does this MR do?

This fixes all of the linting errors with YAML inside GitLab CI templates. These are largely centered around 3 areas:

1. Indentation
2. Comment spacing
3. Trailing spaces and end-of-file blank lines

Explicitly, none of the content of the files is changed, just the formatting.

If you were to run yamllint against it you would still see errors/warnings for document-start (missing ---) and line length. These can be subdued by adding the following extra rules to yamllint:

extends: default
  
rules:
  line-length: disable
  document-start: disable

I would suggest that if wanted we could make some adjustments to the expectations for yaml coding style, however, I fell this decision may be above me at the moment.

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Code review guidelines
• Merge request performance guidelines
• Style guides

Performance and testing

The only additional testing is whether you would look to explictly test your YAML inside the product. Inside GitLab-CI this can be done as follows:

yaml-lint:
  image: sdesbure/yamllint:latest
  script:
    - yamllint .

Security

None required.