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
```
82a239ceb9