[a11y] 9.2.4.1 Areas can be skipped

[tschiebel]

audit: https://infinite.owncloud.com/s/PnaAukHGGsLnrMM

https://bitvtest.de/pruefschritt/bitv-20-web/bitv-20-web-9-2-4-1-bereiche-ueberspringbar

Personal, Shares, Deleted Files

• In the "main" area of the page there is a navigation without a name. As this is a
  a breadcrumb navigation, you could use the "aria-label" attribute to give the element a name such as
  attribute to give the element a name such as "You are here" or similar.

[pascalwengerter]

OcBreadcrumb.vue needs prop for aria-label