Issue title: [CI] 22-10-Logstash failure due to no latest tag for logstash image
 Issue body: 22-10-Logstash is consistent failure in CI testing recently, and the root cause is that the test scripts is using the lastest tag of logstash, however, logstash does not support lastest tag any more. Details, refer to https://hub.docker.com/_/logstash/.  We could use 6.4.1 for our testing.
logs: https://ci-vic.vmware.com/vmware/vic/20373
 Comments: 
 Comment 0: PR is https://github.com/vmware/vic/pull/8385. Close it now.
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