SourcePackageRelease security adapter is unused

[Celso Providelo]

There is a type in the code (s/userfor/usedfor) which indicates the security adapter is not being used as expected, and also that it wasn't tested at all.

Further investigation revealed that not information was leaked because SPRs are not directly exposed in the UI and the related available objects (publishing and build records) reuse the security-adapter code in place (which is correct and covered by tests).

While in this area, we can remove the SPR._cached_publishing_archives and fix up the callsites (theoretically only the SPR security-adapter) because now that security adapters results are cached at the storm cache level, this deprecated property does not represent any performance gain anymore.

[Celso Providelo (cprov)]

To be done sooner than later, but doesn't represent any major problem or information leak (no CP required either).

[Celso Providelo (cprov)]

RF 7545