Fix when context entity "name" not cached

[j0yu]

From wwfxuk#7

Fixed

• Missing context "name" when not found from path cache

Traceback (most recent call last):
  File "/path/to/tk-framework-qtwidgets.git/v2.9.3/python/context_selector/context_widget.py", line 638, in _on_entity_activated
    self._on_context_activated(context)
  File "/path/to/tk-framework-qtwidgets.git/v2.9.3/python/context_selector/context_widget.py", line 629, in _on_context_activated
    self._show_context(context)
  File "/path/to/tk-framework-qtwidgets.git/v2.9.3/python/context_selector/context_widget.py", line 846, in _show_context
    link_display = _get_link_display(context)
  File "/path/to/tk-framework-qtwidgets.git/v2.9.3/python/context_selector/context_widget.py", line 908, in _get_link_display
    entity_name = entity["name"]
KeyError: 'name'

This can happen when the folders for an entity have not been created yet via tank folder, or if there's something wrong with path cache synchronisation.

The fix focuses on making sure the GUI does not break under these circumstances.

[zavinator]

Why this fix is still not merged into master?
The standalone publisher can't be used (because of this bug) for example for linking with CustomEntity that has no work files (so it is not cached)...

[zavinator]

it is fixed since v2.10.8