fix(a11y): added row as role

[qub1t]

row="columnheader" needs a parent with a role="row"

Before submitting a pull request, please make sure you have at least performed the following:

• read and followed the CONTRIBUTING.md guide.
• built and tested the changes locally.
• [] added/updated any applicable tests.
• [] added/updated any applicable API documentation.
• [] added/updated any applicable demos.

[codecov-io]

Codecov Report

Merging #3361 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3361   +/-   ##
=======================================
  Coverage   90.88%   90.88%           
=======================================
  Files          95       95           
  Lines        2743     2743           
  Branches      510      510           
=======================================
  Hits         2493     2493           
  Misses        190      190           
  Partials       60       60

Flag	Coverage Δ
#e2e	55.01% <ø> (ø)	⬆️
#unit	87.99% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
src/datepicker/datepicker-month-view.ts	100% <ø> (ø)	⬆️

---

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 c7bc4d7...b55de2b. Read the comment docs.

[benouat]

LGTM! 👍 will merge