* Use cert-manager to generate certs for tests
* Install Cert-Manager in test env
### Motivation
Currently, we use hard coded certificates for the tests. Instead, we can use Cert Manager to generate the certificates. The primary benefit of this change is that it ensure we're testing the cert manager integration.
### Modifications
* Remove `.ci/tls` directory since we no longer need these certs.
* Remove `scripts/pulsar/clean_tls.sh` (it wasn't used)
* Remove `scripts/pulsar/upload_tls.sh` since we are not uploading any certs
* Update the `helm.sh` test script
* Update the `.ci/clusters` configurations to generate the relevant cert manager manifests
### Verifying this change
- [ ] Make sure that the change passes the CI checks.
* Bump version to `2.9.2`
* Because the latest Pulsar image is based on Java 11, some JVM param for printing GC information has been abandoned, change to use the new JVM param. refer to https://docs.oracle.com/en/java/javase/11/tools/java.html#GUID-BE93ABDC-999C-4CB5-A88B-1994AAAC74D5 and https://issues.redhat.com/browse/CLOUD-3040.
original param | new param
--|--
`-XX:+PrintGCDetails` | `-Xlog:gc*`
`-XX:+PrintGCApplicationStoppedTime` | `-Xlog:safepoint`
`-XX:+PrintHeapAtGC` | `-Xlog:gc+heap=trace`
`-XX:+PrintGCTimeStamps` | `-Xlog:gc::utctime`
* remove JVM param `-XX:G1LogLevel=finest`
