[a11y] 9.2.5.3 Visible labeling part of the accessible name

[tschiebel]

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

https://bitvtest.de/pruefschritt/bitv-20-web/bitv-20-web-9-2-5-3-sichtbare-beschriftung-teil-des-zugaenglichen-namens

Personal

• In the "Keywords" area, the combo box element has a visual text
  "Adding or editing keywords", but this does not appear in the accessible name of the
  element, as it is overwritten by the use of the "aria-label" attribute.
  attribute.
  

Spaces

• In the "Quota for Space 8A - Change art" dialog, the visible label of the "Quota" field is changed by using the
  Quota" field is overwritten by using the "aria-label" attribute "Search for option".
  is overwritten.

Account

• The visible label of the "Language" field is overwritten by the use of the "aria-label"
  attribute "Search for option".

[pascalwengerter]

Looks like the OcSelect.vue default aria-label of "Search for an option" is problematic. Let's add a prop to pass a label to the component, then?