Fix duplicate thumbnails for PDFs

[laritakr]

When text extraction fails on a PDF, the derivative job resubmits. This was resulting in 5 Hyrax::FileMetadata objects on a file set, all for the same thumbnail file, because jobs automatically resubmit 5 times.

In this PR, I commented out the failing extract_full_text method, but also qualified the thumbnail creation on whether the thumbnail is already there.

Screenshots

BEFORE

AFTER

[github-actions]

Test Results

    3 files  ±0      3 suites  ±0   17m 32s ⏱️ -41s
2 027 tests ±0  1 983 ✅ ±0  44 💤 ±0  0 ❌ ±0 
2 054 runs  ±0  2 008 ✅ ±0  46 💤 ±0  0 ❌ ±0 

Results for commit 3a53fd4. ± Comparison against base commit d700f82.

This pull request removes 42 and adds 42 tests. Note that renamed tests count towards both.

spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to destroy 045f2a0a-6b0b-4b18-9dad-33049a6f0692
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to edit d41ce974-27d5-4ec4-b594-33a597b741a9
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to read c52d8261-faef-4fa0-8f1c-8b426a441e63
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to update 059b321a-0df5-4d24-9e9b-ebe7ff471678
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to destroy 37a9fb8a-b658-46c0-b0b4-2337e17477e0
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to edit d7980c34-b39b-4b47-9040-95f85ab51258
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to read 95b7d4a4-e03e-4ec6-a4e9-cad942d380d9
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to update e284991a-c1e7-4367-a844-ce20dcc94dff
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor GenericWork permissions is expected not to be able to destroy 8da00f81-2782-443a-b0dd-d1cdfdc6e27a
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor GenericWork permissions is expected not to be able to edit 903bd28d-76b8-44fa-af30-3d965080446f
…

spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to destroy ae2027e7-41a6-4563-8e38-64382d085470
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to edit 85e0e841-94b5-4232-8460-ea5907f8bfd9
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to read 6b60de30-d0c1-4a51-b118-1034e28cb02b
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor Etd permissions is expected not to be able to update c2a754dc-2fa5-4e13-99e3-15041f5bfa7f
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to destroy a0c2973a-efa5-4fca-a525-71a2d4338fab
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to edit a7d15699-026d-407a-9074-58b761ecc7ce
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to read 957f86f5-c26c-4199-8c70-238c2a6a906a
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor FileSet permissions is expected not to be able to update 1a8660a6-26b6-4295-bc9e-213c9ef67be6
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor GenericWork permissions is expected not to be able to destroy 6d7f2c96-00c6-49af-bab0-679ecab9f51d
spec.abilities.work_ability_spec ‑ Hyrax::Ability::WorkAbility when work depositor GenericWork permissions is expected not to be able to edit 45b1d792-5acd-4948-98ce-32781939a62f
…

♻️ This comment has been updated with latest results.