Clickhouse storage configuration prefers global value

[npalladium]

Given the following values:

global:
  storageClass: global-value
clickhouse:
  enabled: true
  persistence:
    storageClass: other-value

The Clickhouse Installation will use global-value as the storage class instead of other-value.

This is because the code has {{- $storageClass := default .Values.persistence.storageClass .Values.global.storageClass -}}. The default function is to be used like default DEFAULT_VALUE GIVEN_VALUE (which is kinda unlike every other language, but makes sense as it is designed to be used with |).

If the global value being preferred is the intended behaviour, it should be pointed out clearly because that is unexpected.