office-ui-fabric-react v6.189.0

Minor changes

• adding missing filetype mappings to support LPC and other partners (commit by tachtevrenidis, pr #9320)
• Fix TS 3.5 typing issues. (commit by JasonGore, pr #9336)
• Consume Selection from Utilities (commit by ThomasMichon, pr #9303)

Patches

• BaseButton: Render placeholder icon if iconName is empty string (commit by leddie24, pr #9330)
• ContextualMenu: When menus are rendered with the persistMenu flag, the scrollbar now renders correctly in Edge. (commit by jdhuntington, pr #9124)
• add tooltips to Calendar buttons without text (commit by lorejoh12, pr #9328)
• TextField: Adds aria-labelledby to input (commit by staciecarroll, pr #9248)