Support transformer replace action

[dongjiang1989]

/area interceptor

Describe the feature

support replace action. like: strings.Replace(...)

like: https://grafana.com/docs/loki/latest/clients/promtail/stages/replace/

interceptors:
  - type: transformer
    actions:
      - action: replace(body)
        old: "abc"
        new: "ABC"
      ...

input:

{
  "body": "2023-09-04T09:21:20.545525544Z DEBUG abc"
}

output:

{
  "body": "2023-09-04T09:21:20.545525544Z DEBUG ABC"
}