Migrate AATH to use fully qualified credential identifiers instead of indy identifiers

[nodlesh]

As @genaris has mentioned in #666

... it is related to openwallet-foundation/credo-ts#1391. AFJ as issuer is not currently working in AATH because it uses legacy/unqualified identifiers and AFJ switched to support only fully qualified identifiers for issuance, which broke several runsets some weeks ago.

While it is still possible to change backchannel input/output processing to make it work, I think would be better to solve the issue (or find a more straighforward solution for this) in AFJ side, and update backchannel if needed.

[swcurran]

I think the better approach is to use fully qualified names in the test harness, since that is The Right Way to do things, and to fix any backchannels that break as a result. AFJ would not need to be fixed.