bump parent to 11.0.21 to fix jackson-databind-cve

[naveenmall11]

Problem

https://confluentinc.atlassian.net/browse/CC-18965

Solution

Update the parent version to 11.0.21 https://github.com/confluentinc/kafka-connect-storage-common/pull/308

Use url directly https://github.com/confluentinc/kafka-connect-storage-cloud/pull/618

Does this solution apply anywhere else?

• [ ] yes
• [ ] no

If yes, where?

Test Strategy

Testing done:

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

Release Plan

[venkatteki]

@snehashisp @sudeshwasnik can one of you please review this PR (seems team1 approval is mandatory)

[janjwerner-confluent]

This was resolved in #656