Update a streaming audit event header

Overview

Once it is possible to create a streaming audit event HTTP header, it should be possible to update the same header via the GraphQL API.

Proposal

• Create a GraphQL mutation to update a streaming audit event HTTP header.

mutation {
  externalAuditEventDestinationHeaderDestroy(input: { desintationID: "gid://gitlab/somethingsomething/Destination/2, headerID: "gid://id/to/header", key: "NEW_KEY", value: "NEW_VALUE" } ) {
    errors
  }
}