Don't throw errors on LdpService actions

Calls to LdpResourceService or LdpContainerService (such as `ldp.resource.get`) should never throw errors, but instead return the result of the operation.

When an errror is thrown, the whole process is halted. It is not what you'd expect for simply querying a non-existent file, for example.

Start by locating the LdpResourceService and LdpContainerService actions, including `ldp.resource.get`, and inspect how they handle a query for a non-existent file. Verify that these actions return the operation result without throwing or halting the process.

Written by the indexing model from the issue text.