fix(Menu): Add aria posinset and setsize, hide indicator from narration

[jurokapsiar]

This fixes menu items narration especially for older versions of Chromium.

• explicitly adds aria-posinset and aria-setsize attributes to the menu item root
• changes default behavior of Indicator component to IconBehavior

Might also fix #982 (but verification is needed)

[codecov]

Codecov Report

Merging #1066 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1066      +/-   ##
==========================================
+ Coverage   81.89%   81.91%   +0.01%     
==========================================
  Files         693      693              
  Lines        8447     8450       +3     
  Branches     1233     1233              
==========================================
+ Hits         6918     6922       +4     
+ Misses       1514     1513       -1     
  Partials       15       15

Impacted Files	Coverage Δ
...b/accessibility/Behaviors/Menu/menuItemBehavior.ts	100% <ø> (ø)	⬆️
packages/react/src/components/Menu/MenuItem.tsx	63.11% <ø> (ø)	⬆️
...kages/react/src/components/Indicator/Indicator.tsx	77.77% <100%> (ø)	⬆️
packages/react/src/components/Menu/Menu.tsx	90.56% <100%> (+2.56%)	⬆️

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[miroslavstastny]

👍 for code changes
@kolaps33 could you please review/verify accessibility?

[layershifter]

These props will be added to public API actually, I'm fine with this for now, but I'm not sure that components should be so coupled with accessibility concerns.

[jurokapsiar]

yes, I am aware. but as far as I know, we do not have any other option to pass the information from parent menu to the menu item behaviors.

[kolaps33]

Tested with following:
ElectronFiddle + Jaws a NVDA
Fx + NVDA 
Ch + NVDA
Edge + Narrator

narrating position correctly :)

OSX/Chrome/VoiceOver still exists the issue:
#982