feat: add GitHub Actions for Markdown, YAML and trailing whitespace linting

[jbampton]

…inting

Contributor Checklist

• I have run the tests locally and they passed. (refer to testing section in contributing)
• I have added tests, or extended existing tests, to cover any new features or bugs fixed in this PR

optionals

• I have added entry in the CHANGELOG.md
• If this PR needs a follow-up in dash docs, community thread, I have mentioned the relevant URLS as follows
  • this GitHub #PR number updates the dash docs
  • here is the show and tell thread in Plotly Dash community

[gvwilson]

hi @T4rk1n - is this one still useful or has it gone stale?

[T4rk1n]

This is stale, I don't think we want decouple linting from the rest of our CI yet.