FIO-7292: Added own check to delete file from storage

[roma-formio]

Link to Jira Ticket

https://formio.atlassian.net/browse/FIO-7292

Description

We have special entity with 'submission' type and empty id to check file permissions. So added missing delete check to have ability delete file from storage with delete_own permission.

Checklist:

• I have completed the above PR template
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if applicable)
• My changes generate no new warnings
• My changes include tests that prove my fix is effective (or that my feature works as intended)
• New and existing unit/integration tests pass locally with my changes
• Any dependent changes have corresponding PRs that are listed above