Non-admin user cannot view attachments from an automated suite when result publisher was in light mode

Affected version : 6.0.1

Observed behaviour

This bug ticket follows on from the : #57 (closed)

When a non-admin user tries to preview or download an automated execution report from a project where result publisher was in 'light' mode, the same error occurs again:

error 500 + log :

[24-03-18 16:07:43.516] SquashTM - 4648 ERROR [http-nio-8080-exec-3] [ServletWebRequest: uri=/squash/backend/file-viewer/attachment/82/CT_Cucumber%5B23%5D-report.xml;client=83.142.151.154;session=81EE7C7BDF19EF5D831F1C986D45A5EB;user=XDE_cdp] --- org.squashtest.tm.web.backend.exceptionresolver.HandlerExceptionLogger: An exception occured while processing request  : https://013e-83-142-151-154.ngrok-free.app/squash/backend/file-viewer/attachment/82/CT_Cucumber%5B23%5D-report.xml
org.springframework.dao.InvalidDataAccessApiUsageException: No entity class holder found for attachment list id : 65; nested exception is java.lang.IllegalArgumentException: No entity class holder found for attachment list id : 65

Note: No problem when result publisher was set to full mode (which was verified on the ticket above).

Steps to reproduce

From a Squash v5.X :

• have a project and set the 'result publisher' plugin to light mode and in this project :
  • run automated tests (any technology) with a user other than the administrator, the reports can be downloaded.
• upgrade to Squash 6.0.1 + result publisher 6.0.1
• log on with a user other than admin, then go to the project that was previously set up with result publisher in light mode
• try to preview or download an automated exec report -> this is not possible

Expected result

A non-administrator user should be able to download an old execution report even if its project was configured with light results reporting (result publisher plugin).