[blocking release 1.13] Should DontAllowInsecureCSRUsageDefinition be renamed or replaced with a opt-in flag?

[inteon]

Before we release 1.13, we have should revisit the DontAllowInsecureCSRUsageDefinition feature flags that were added in #6182 and #6199.

Context: #6182 (comment) and #6199 (comment)

We want to consider the following options:

• replace the feature flag with an opt-in flag --allow-insecure-csr-usage-defintions
• rename DontAllowInsecureCSRUsageDefinition to DisallowInsecureCSRUsageDefinition

A feature flag makes it easy to remove this option in the future. However, having a feature gate which is immediate GA in the next available version might not feel right either.

[inteon]

In todays stand-up, we agreed that we can continue with a feature gate (which will make it easy to remove this option in the future).
We still have to:

• rename DontAllowInsecureCSRUsageDefinition to DisallowInsecureCSRUsageDefinition
• change the feature gate type to Beta instead of GA