feat(configx): add HTTP header log redaction config

[whisky-is-life]

This PR introduces a change that allows configuration of additional HTTP headers to be redacted in the logs to address a case where custom HTTP headers containing sensitive information (e.g. tokens) are logged on production environments when a deployment such as one for Ory Kratos triggers a webhook request with these headers

Some alternatives that were considered include:

• Setting the log level to fatal to keep these kind of information out of the logs, which is not really a desirable log level as it would result in decreased observability of the deployments
• Trying to place tokens inside of the Authorization header, which would be ideal, but some 3rd party APIs do not accept a standard Authorization header and instead require non-standard HTTP headers such as X-Auth-Token in which case it is simpler to have deployments accept such headers with redaction, rather than having some proxy rewrite the HTTP headers

Related Issue or Design Document

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