Fix based_volumes sublist

[Ladas]

Fix based_volumes sublist.

Fixes:
https://bugzilla.redhat.com/show_bug.cgi?id=1449294

And also new bug introduced by doing 2nd rendering of the table using report_data

[Ladas]

before:

throws an exception

after:

[miq-bot]

Checked commits Ladas/manageiq-ui-classic@dac84e8~...f67b0d1 with ruby 2.2.6, rubocop 0.47.1, and haml-lint 0.20.0
2 files checked, 0 offenses detected
Everything looks fine. ⭐

[Ladas]

@martinpovolny @karelhala are we working on the issue of not rendering the tables more than once? Now it goes all the way through the generic_show_mixing, then there seems to be a new way using report_data method, that uses new mappings for exceptions the generic mixin was trying catch. And since we just turned this by default, more pages might be broken, e.g. all that are using a specific association
https://github.com/Ladas/manageiq-ui-classic/blob/36c5a957b6fcad6a89d81bb8238c70ef04a55d1e/app/controllers/mixins/generic_show_mixin.rb#L151 or even model.

Also I was trying to do at least basic integration specs for rendering of the tables, e.g. https://github.com/Ladas/manageiq-ui-classic/blob/48830b68883f97eab15533375474b8dca8992e39/spec/shared/controllers/shared_examples_for_network_port_controller.rb#L48 , do we have something similar for the report_data method? Or it's all untested again? Also those table specs should have been enhance to test e.g. filtering and ordering. These are the parts we are breaking over and over again. :-(

[martinpovolny]

should we add the assert_nested_list test?

[Ladas]

@martinpovolny we should add the test indeed :-)

[simaishi]

@Ladas MODEL_STRING doesn't exist in Fine branch and I'm not sure where the changes should go. Please create a PR for Fine branch.

[Ladas]

@simaishi #2731

[simaishi]

Backported to Fine via #2731