chore(openapi): update registryinstance/v1 OpenAPI document + generation changes 2 (#647)

* chore(openapi): update registryinstance/v1 OpenAPI document

* fix: modify generated code to support custom content type

* fix: remove content type replace preprocessing

* fix: update registry instance schema preprocessing

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Co-authored-by: app-services-ci <app-services-ci@users.noreply.github.com>

Author: jsenko