feat: add a categories formatter

[abdelkd]

Description
This PR will add the ability to change the legend on AreaChart using categoryFormatter prop

• I added a new prop to BaseChartProps
• Changed ValueFormatter type to accept generic type but fallback to default one
• Added a new story

Related issue(s)
#825

What kind of change does this PR introduce? (check at least one)

• Bug fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• New Feature (BREAKING CHANGE which adds functionality)
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change? (check one)

• Yes
• No

If yes, please describe the impact and migration path for existing applications:

How has this been tested?
yes, I've added a new story which uses a function on src/stories/chart-elements/helpers/utils.ts which changes the categories to uppercase

Screenshots (if appropriate):

The PR fulfils these requirements:

• It's submitted to the main branch
• When resolving a specific issue, it's referenced in the related issue section above
• My change requires a change to the documentation. (Managed by Tremor Team)
• I have added tests to cover my changes
• Check the "Allow edits from maintainers" option while creating your PR.
• Add refs #XXX or fixes #XXX to the related issue section if your PR refers to or fixes an issue.
• By contributing to Tremor, you confirm that you have read and agreed to Tremor's CONTRIBUTING.md guideline. You also agree that your contributions will be licensed under the Apache License 2.0 license.

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Name	Status	Preview	Comments	Updated (UTC)
tremor-storybook	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Dec 20, 2023 8:06pm

[Erasmus001]

great