feat(slider): expose formatLabel to value tooltip

[dkaushik95]

This PR exposes formatLabel to the tooltip for devs to use

• expose formatLabel to thumbWrapper for twoHandles as well as single handle.
• add examples on storybooks on how it could be used

Doesn't close a PR but gets us closer to the comment here: https://github.com/carbon-design-system/carbon/issues/7581#issuecomment-1113437295

Changelog

New

• formatLabel now also works with the Tooltips for the thumbs which gives you more options on how to customize how the value looks.
• Two new storybooks added to describe the change

Changed

• Changed the definition of formatLabel to represent the above addition

Testing / Reviewing

• Ran unit test to make sure nothing is breaking
• You can test it by changing the storybooks:
  • Slider With Hidden Inputs And Custom Format
  • Slider With Hidden Inputs And Format Label

Screenshots