Caddy returns 200 when 5xx fom upstream about cache-handler HOT 9 CLOSED

apps:
  http:
    servers:
      srv_cache_api:
        listen:
          - :2020
        routes:
          - match:
              - path:
                  - /cache-api*
            handle:
              - handler: cache
      srv_main:
        listen:
          - :80
        automatic_https:
          disable: true
          disable_redirects: true
        routes:
          - handle:
            - handler: cache
            - handler: encode
              encodings:
                gzip: {}
                zstd: {}
              prefer:
                - zstd
                - gzip
            - handler: reverse_proxy
              upstreams:
                - dial: "#{$UPSTREAM}"
        logs:
          default_logger_name: log0

  cache:
    TTL: 1m
    stale: 1m
    log_level: INFO
    api:
      basepath: /cache-api
      souin:
        basepath: /souin
        enable: true
      prometheus:
        basepath: /prometheus
        enable: true

logging:
  logs:
    default:
      writer:
        output: stdout
      level: INFO
      exclude:
        - http.log.access.log0
    error_log:
      writer:
        output: stderr
      level: ERROR
    access:
      writer:
        filename: /var/log/caddy/access.log
        output: file
      level: INFO
      include:
        - http.log.access.log0
admin:
  listen: 0.0.0.0:2019

$ curl -v http://localhost/
*   Trying 127.0.0.1:80...
* Connected to localhost (127.0.0.1) port 80 (#0)
> GET / HTTP/1.1
> Host: localhost
> User-Agent: curl/7.79.1
> Accept: */*
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 200 OK
< Server: Caddy
< Date: Mon, 21 Mar 2022 15:16:21 GMT
< Content-Length: 0
<
* Connection #0 to host localhost left intact

$ curl -v -H "Pragma: no-cache"  http://localhost/
*   Trying 127.0.0.1:80...
* Connected to localhost (127.0.0.1) port 80 (#0)
> GET / HTTP/1.1
> Host: localhost
> User-Agent: curl/7.79.1
> Accept: */*
> Pragma: no-cache
>
* Mark bundle as not supporting multiuse
< HTTP/1.1 502 Bad Gateway
< Cache-Status: Souin; fwd=uri-miss
< Server: Caddy
< Date: Mon, 21 Mar 2022 15:19:09 GMT
< Content-Length: 0
<
* Connection #0 to host localhost left intact