Dependencies: Restore cleanly Oracle Instant Client for thick-mode Oracle connections

[Geogouz]

#421 removed the Oracle Instant Client from the container images making Oracle connectivity depend on python-oracledb thin mode in the main Rucio images.

Although this is breaking the probes image (because there, we still use cx_Oracle), the main problem is that at Cern, the connections are using Encryption service and Crypto-checksumming service which means that in these cases, we do need the thick client.

So I suggest to reintroduce Instant Client, but in a cleaner/pinned way (via Oracle signed package verification). Maybe try to go even with 23ai (which supports 19c or later) to be more future-proof. And then as a second step, change probes from cx_Oracle to python-oracledb.

Here is a draft: #523

Opinion? @bari12 @dchristidis

[bari12]

⚠️ We need to get this out quickly. I was somehow under the impression that we do not need the thick client. By the Monday RC1 release, this needs to be fixed in the container.