Add the ability to define Schema normalization

[yraffin]

Problem

Schema normalization on Schema registry is disabled by default. We might need to enable it for some subjects.

Suggestion

Adding this information in the spec of the Schema resource

---
apiVersion: v1
kind: Schema
metadata:
  name: myPrefix.topic-value # your subject name
spec:
  normalize: true
  schemaFile: schemas/topic.avsc # relative to kafkactl binary

When normalize is true, the API call to post the new subject version will use the query param: normalize=true