[Bookie] Fallback to PULSAR_EXTRA_OPTS if BOOKIE_EXTRA_OPTS isn't defined (#10397)
[Bookie] Fallback to PULSAR_EXTRA_OPTS if BOOKIE_EXTRA_OPTS isn't defined (#10397)

### Motivation

- #9469 introduced a breaking change by changing the behavior . This change was part of 2.7.1 release.

### Modifications

- fallback to `PULSAR_EXTRA_OPTS` if `BOOKIE_EXTRA_OPTS` isn't defined

- don't pass `-Dio.netty.*` system properties if `PULSAR_EXTRA_OPTS` or
  `BOOKIE_EXTRA_OPTS` is set
  - this is to be consistent with `PULSAR_EXTRA_OPTS` behavior and
    to prevent duplicate properties
  - add `-Dio.netty.leakDetectionLevel=disabled` unless `BOOKIE_EXTRA_OPTS`
    is set since `PULSAR_EXTRA_OPTS` doesn't include that setting by default.
   (`simple` is the default if the property isn't set)

### Other context

- It is also necessary to cherry-pick #9621 to restore backwards compatibility in 2.7.x branch.
massakam/pulsar,massakam/pulsar,merlimat/pulsar,merlimat/pulsar,yahoo/pulsar,merlimat/pulsar,massakam/pulsar,yahoo/pulsar,massakam/pulsar,yahoo/pulsar,merlimat/pulsar,massakam/pulsar,yahoo/pulsar,massakam/pulsar,merlimat/pulsar,merlimat/pulsar,yahoo/pulsar,yahoo/pulsar