[Meta][Vis-Builder] Missing functional tests

[ananzh]

• VisBuilder top nav save

  • if the canvas is empty, can not save filter and query updates. This is expected due to empty canvas error The canvas is empty. Add some aggregations before saving
  • if the canvas is not empty, can save filter and query updates.
  • drop a field will enable top nav save
  • remove a field will disable top nav save if vb is not saved; will enable top nav save if vb is saved (change previous save)
  • Issues: [BUG][VisBuilder] Updated filter and query are not savable #5645

• VisBuilder saved object

  • should be able to save filter
  • should be able save query
  • should load saved filter
  • should load saved query
  • Issues: [BUG][VisBuilder] filter (_q) is not saved which causes un-persistent state #5643, [BUG][VisBuilder Migration] Missing filter and query (_q state) when reload a saved legacy vis builder #5646

• VisBuilder embeddable

  • saved filter can be applied to embedded VisBuilder vis in dashboard
  • Issues: [BUG] VisBuilder Embeddable don't have filter and query  #6512

• VisBuilder load

  • when load a vb, _q state should be cleaned (filter and query).
  • when load a vb, _g state should be persistent (time range)
  • Issues: [BUG][VisBuilder] Filter state is not cleaned when change to vis builder #5644