[FIX] Data picker behaviour with non-English

[kubajmarek]

Describe the bug

1. Date picker months aren't Capitalized in other languages. e.g. Polish
2. localizeMonths is only triggered on mount, so it's impossible to change language without rerender

To Reproduce

Steps to reproduce the behavior:
Error 1.

1. Run Component Library
2. In UiDatepicker change lang: 'en-us' to lang: 'pl'
3. Open said story
4. Open calendar
5. Month names are lower cased

Error 2.

1. Go to https://component.infermedica.com/?path=/story/organisms-datepicker--full-configuration
2. Click on props.lang
3. Select any language other than en or en-us
4. See that nothing changes in Month tab

Expected behavior

A clear and concise description of what you expected to happen.

Screenshots

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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context

Add any other context about the problem here.