docs: fix link to orgmode_api.txt

[celsobenedetti]

Summary

36aa2f2 docs: fix lua code for combined agenda view config
bfbd30f docs: fix link to orgmode_api.txt

Currently the link to the txt file results in 404 on the docs:
https://nvim-orgmode.github.io/#api-docs

Related Issues

n/a

Changes

Just docs tweaks

Checklist

I confirm that I have:

• Followed the
  Conventional Commits
  specification (e.g., feat: add new feature, fix: correct bug,
  docs: update documentation).
• My PR title also follows the conventional commits specification.
• Updated relevant documentation, if necessary.
• Thoroughly tested my changes.
• Added tests (if applicable) and verified existing tests pass with
  make test.
• Checked for breaking changes and documented them, if any.

[kristijanhusak]

Thanks!