Update confluentinc/cp-base-new Docker tag to v7.5.1

This MR contains the following updates:

Package	Type	Update	Change
confluentinc/cp-base-new	ironbank-docker	minor	7.4.2 -> 7.5.1
confluentinc/cp-base-new	stage	minor	7.4.2 -> 7.5.1

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