Make set today button works properly with autoOk

[dmtrKovalenko]

This PR closes #1553

Description

Properly accept date using Today button instead of just update value.

[vercel]

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🔍 Inspect: https://zeit.co/mui-org/material-ui-pickers/m6mb2krl7
✅ Preview: https://material-ui-pickers-git-chore-settoday-with-autook.mui-org.now.sh

[cypress]

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Test summary

61 • 0 • 0 • 0

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Run details

Project	material-ui-pickers
Status	Passed
Commit	51cdcaa
Started	Mar 3, 2020 11:57 AM
Ended	Mar 3, 2020 11:58 AM
Duration	01:08 💡
OS	Linux Debian - 9.11
Browser	Chrome 78

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[codecov]

Codecov Report

Merging #1555 into next will increase coverage by 0.12%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##             next    #1555      +/-   ##
==========================================
+ Coverage   91.88%   92.01%   +0.12%     
==========================================
  Files          63       63              
  Lines        1763     1765       +2     
  Branches      304      305       +1     
==========================================
+ Hits         1620     1624       +4     
+ Misses        109      108       -1     
+ Partials       34       33       -1

Impacted Files	Coverage Δ
lib/src/_shared/ModalDialog.tsx	100% <ø> (ø)	⬆️
lib/src/_shared/hooks/useViews.tsx	95.83% <100%> (ø)	⬆️
lib/src/_shared/hooks/usePickerState.ts	89.06% <100%> (+1.96%)	⬆️
lib/src/views/Calendar/CalendarView.tsx	82.05% <0%> (+1.28%)	⬆️

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