Remove unnecessary utf-8 header in license_headers.py (follow-up to #615)

[jayaddison]

Description

This is a small followup to @samuelorji's cleanup in #615. It applies the same cleanup (removal of a redundant/default coding declaration of utf-8 in source files) to the license_headers.py check script itself.

This pull request also removes that line from the list of LINES_TO_KEEP - lines of source code that aren't checked by the license check script - since it shouldn't appear anymore.

Issues Resolved

613

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (6f26eb3) 71.98% compared to head (6b876d3) 71.98%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #617 +/- ## ======================================= Coverage 71.98% 71.98% ======================================= Files 89 89 Lines 7935 7935 ======================================= Hits 5712 5712 Misses 2223 2223 ```

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[saimedhi]

@jayaddison, I think changelog entry is not needed.

[dblock]

I opened two more issues related to API generator, #619 and #618, if you have any interest @jayaddison :)

[jayaddison]

Thanks @saimedhi - I had pushed a commit with a changelog entry a few moments before seeing that you added a label to skip it. It was merged - I hope that's OK?

@dblock those issues do look interesting, thanks; I cannot offer any sense of when I might work on them yet, though.

Something that I notice about the utils/generate_api.py script is that it could be difficult to easily confirm what version (git commit ID) of the OpenSearch.openapi.json spec file was used to produce the output. Has including a version/commit identifier, or referencing the spec file using a git submodule been considered?

[dblock]

I would largely prefer a submodule for the exact reason you describe. Feel free to open a feature request or just do it (TM).