fix: picker: ensure keyboard navigation selected styles are implemented in year mode

[dkilgore-eightfold]

SUMMARY:

Date Picker supports keyboard navigation, but year mode needs fixing:
Adds selected class names to picker year mode.

yearMode.mp4

GITHUB ISSUE (Open Source Contributors)

#501

JIRA TASK (Eightfold Employees Only):

CHANGE TYPE:

• Bugfix Pull Request
• Feature Pull Request

TEST COVERAGE:

TODO: Add keyboard navigation tests (Jest)

TEST PLAN:

Pull the PR branch and run yarn and yarn storybook. test Date Picker keyboard navigation:

Tab - Places focus on the calendar in the dropdown

Date mode:
Arrow left - Previous day
Arrow right - Next day
Arrow down - Next week
Arrow up - Previous week
Page down - Next month
Page up - previous month
CTRL + Arrow left - Previous year
CTRL + Arrow right - Next year

Week mode:
Arrow left - N/A
Arrow right - N/A
Arrow down - Next week
Arrow up - Previous week
Page down - Next month
Page up - previous month
CTRL + Arrow left - Previous year
CTRL + Arrow right - Next year

Month mode:
Arrow left - Previous month
Arrow right - Next month
Arrow down - Next month row
Arrow up - Previous month row
CTRL + Arrow left - Previous year
CTRL + Arrow right - Next year
Page down - N/A
Page up - N/A

Year mode:
Arrow left - Previous year
Arrow right - Next year
Arrow down - Next year row
Arrow up - Previous year row
CTRL + Arrow left - Previous decade
CTRL + Arrow right - Next decade
Page down - N/A
Page up - N/A

Decade mode:
Arrow left - Previous decade
Arrow right - Next decade
Arrow down - Next decade row
Arrow up - Previous decade row
CTRL + Arrow left - Previous century
CTRL + Arrow right - Next century
Page down - N/A
Page up - N/A

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit abb43c9:

Sandbox	Source
React	Configuration
Vanilla	Configuration

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (main@3a29afd). Click here to learn what that means.
Patch has no changes to coverable lines.

📣 This organization is not using Codecov’s GitHub App Integration. We recommend you install it so Codecov can continue to function properly for your repositories. Learn more

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #523   +/-   ##
=======================================
  Coverage        ?   84.84%           
=======================================
  Files           ?      789           
  Lines           ?    16550           
  Branches        ?     5737           
=======================================
  Hits            ?    14042           
  Misses          ?     2441           
  Partials        ?       67           

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.