[pickers] Allow nested LocalizationProvider

[flaviendelangle]

Part of #5844

This PR focuses on supporting nested LocalizationProvider so that we can add a small wrapper on all pickers component calling LocalizationProvider with props.localeText.
This will also allow users to create one top level LocalizationProvider with the adapter (or even in the theme) and create LocalizationProvider deeper in the tree if they want to adapter the adapterLocale or the localeText.

I added le localeText on DesktopDatePickers for demonstration purpose.

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• Remove LocalizationProvider['locale']

[mui-bot]

These are the results for the performance tests:

Test case	Unit	Min	Max	Median	Mean	σ
Filter 100k rows	ms	505.5	974.9	653.3	719.36	192.316
Sort 100k rows	ms	671.9	1,174.3	1,174.3	964.74	179.583
Select 100k rows	ms	220.8	308.5	284.9	269.12	37.338
Deselect 100k rows	ms	133.7	202.6	150.3	164.4	29.983

Generated by 🚫 dangerJS against 9afbc8d

[alexfauquette]

Sounds good 👍

[flaviendelangle]

I'm removing the localeText of DesktopDatePicker
I'll add it to all components in a follow up PR, it was just for demonstration purpose.