[Test - do not merge] Update Jenkinsfile to docker-debian-jdk8

[bennettzhu1]

Problem

docker-oraclejdk8 is an EOL debian 8 distribution that is deployed on the jenkins hosts but was removed in the docker-build-images repo. This makes supporting it very difficult, and one issue is the jenkins job fails to pull the latest common-tools version which is needed in the standard jenkins build logic.

Solution

Use the docker-debian-jdk8 node instead of docker-oraclejdk8. The images are very similar and this approach has worked before:

https://github.com/confluentinc/kafka-connect-bigquerystorage-sink/pull/5 https://github.com/confluentinc/kafka-connect-sqs/pull/30

Does this solution apply anywhere else?

• [x] yes
• [ ] no

If yes, where?

https://github.com/search?q=org%3Aconfluentinc+docker-oraclejdk8+NOT+is%3Aarchived&type=code

Test Strategy

PR build works

Testing done:

• [ ] Unit tests
• [ ] Integration tests
• [ ] System tests
• [ ] Manual tests

Release Plan

Merge to master and monitor the pipelines. This is relatively low risk since it only affects the jenkins agent so rollback is straightforward](https://github.com/search?q=org%3Aconfluentinc+docker-oraclejdk8+NOT+is%3Aarchived&type=code)

[CLAassistant]

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0 out of 4 committers have signed the CLA.

:x: ConfluentJenkins
:x: b-goyal
:x: bennettzhu1
:x: sp-gupta
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