Drawer panel updates

[mattnolting]

• https://www.patternfly.org/v4/documentation/react/components/drawer#static-drawer has hidden="" aria-hidden="true" aria-expanded="false" set by default

• pf-c-drawer__panel only needs to toggle hidden attribute. aria-hidden="true" aria-expanded="false" can be removed

[boaz0]

@tlabaj can I work on it?

[tlabaj]

@boaz. Sure!