[DatePicker] Add test for textbox aria-invalid

[PaulSavignano]

• Tests aria-invalid attribute on the DatePicker's input element when the locale is updated and the date becomes invalid through incorrect text input.

• Add test test for Wrong value of isValid() when using DE #1895 (Fix/add locale to parse dmtrKovalenko/date-io#406)

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[cypress]

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Test summary

78 • 0 • 3 • 0

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Run details

Project	material-ui-pickers
Status	Passed
Commit	cf31b5c
Started	Jul 31, 2020 12:06 PM
Ended	Jul 31, 2020 12:08 PM
Duration	01:34 💡
OS	Linux Debian - 10.0
Browser	Chrome 80

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[dmtrKovalenko]

Thanks, this test case is definitely nice to have. Added a couple of comments how to make tests more readable.

[oliviertassinari]

Great start :)

[dmtrKovalenko]

Am I the only who cannot see the changes of this PR?

[PaulSavignano]

@dmtrKovalenko, During a revert to an earlier commit my local git became out of sync and would not pull in changes from the next branch. I was unable to merge and ran a reset.

While running tests with luxon and moment the test for valid after invalid fails with locale de. I can look into this further if you'd like.

[oliviertassinari]

I have left a few comments, we are almost there :).

[oliviertassinari]

@dmtrKovalenko Dayjs tests were running with date-fns

updated

[dmtrKovalenko]

Thanks for this awesome tests!