Automatic merge from submit-queue (batch tested with PRs 45852, 45965, 45941)

Examples: fixed cassandra mirror detection that assumes an FTP site will always be presented

**What this PR does / why we need it**:
This fixes regressions in the cassandra example docker image creation scripts

**Which issue this PR fixes** : #45882

**Special notes for your reviewer**:
Pound that accept button, it will be fine.

**Release note**:

```
Fixed the cassandra docker image cassandra mirror detection logic
bumped cassandra to v3.10, as v3.9 is no longer on the mirrors
bumped ubuntu-slim to v0.9
```