feat: make sensitive log value redaction text configurable

[aarmam]

This pull request introduces feature to configure sensitive log value redaction text. Current redaction text "Value is sensitive and has been redacted. To see the value set config key "log.leak_sensitive_values = true" or environment variable "LOG_LEAK_SENSITIVE_VALUES=true"." is too long and takes considerable amount of log space.

Related issue(s)

ory/x#482

Checklist

• I have read the contributing guidelines.
• I have referenced an issue containing the design document if my change
  introduces a new feature.
• I am following the
  contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security. vulnerability, I
  confirm that I got green light (please contact
  security@ory.sh) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

[zepatrik]

Nice, thank you 👍