Remove abandoned / stale cache files

handle abandoned cache files:

• objects in cache but not in hardening manifest now removed
• objects in cache but ENABLE_CACHE unset now removed

also cleaned up some logging / print statements

tests:

ENABLE_CACHE not set

• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286047
• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286069 (new container + file)
• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286089 (remove container + file)

ENABLE_CACHE set

• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286108 (initial cache creation)
• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286128 (new container + file)
• https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286147 (remove container + file)

ENABLE_CACHE not set

https://code-ib-zelda.staging.dso.mil/dsop/c.geary/pipeline-runner-alpine-dev/-/jobs/286166 (abandons all cached items)