feat(menu): Remove Children API examples

[miroslavstastny]

Menu

Removes all Children API examples for Menu component as these are currently unsupported and broken.

TODO

• Conformance test
• Minimal doc site example
• Stardust base theme
• Teams Light theme
• Teams Dark theme
• Teams Contrast theme
• Confirm RTL usage
• W3 accessibility check
• Stardust accessibility check
• Update glossary props table
• Update the CHANGELOG.md

[codecov]

Codecov Report

Merging #111 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #111   +/-   ##
=======================================
  Coverage   86.05%   86.05%           
=======================================
  Files          39       39           
  Lines         667      667           
  Branches      102      102           
=======================================
  Hits          574      574           
  Misses         90       90           
  Partials        3        3

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 321d5f7...957cef7. Read the comment docs.

[alinais]

Let's sync with the team and @levithomason to decide whether we'd like to remove the children handling at all for Menu component.
Meantime, this PR looks good to me.

[kuzhelov]

please, just add changes to CHANGELOG and we can merge 👍