Feature request for merge_all aggregate action

Is your feature request related to a problem? Please describe.
It would be nice to have a merge aggregate action. There is no way to preserve values from different events in aggregate action for non identification_keys fields though they may contain useful data.

Describe the solution you'd like
Proposing a merge_all action which needs data_types for fields which we want to merge. The data type is needed for doing object comparisons.

Pipeline

aggregation-pipeline:
  workers: 2
  delay: "1000"
  source:
    file:
      path: /usr/share/data-prepper/files/example.log
      format: json
      record_type: event
  processor:
    - aggregate:
        identification_keys: ["ipv4_src_addr", "l4_src_port", "ipv4_dst_addr", "l4_dst_port", "protocol", "in_bytes", "in_pkts"]
        group_duration: 4s
        action:
          merge_all:
            data_types:
              output_snmp: "integer"
              flow_seq_num: "integer"
              src_tos: "integer"
              input_snmp: "integer"
              l4_dst_port: "integer"
              tcp_flags: "integer"
              in_bytes: "integer"
              in_pkts: "integer"
              protocol: "integer"
              flowset_id: "integer"
              version: "integer"
              dst_as: "integer"
              ip_dscp: "integer"
              l4_src_port: "integer"
              ipv4_src_addr: "string"
              first_switched: "string"
              last_switched: "string"
              ipv4_dst_addr: "string"
  sink:
    - stdout:

Input

{"output_snmp": 2, "flow_seq_num": 700710, "src_tos": 64, "input_snmp": 10, "l4_dst_port": 22, "tcp_flags": 16, "in_bytes": 40, "in_pkts": 1, "ipv4_src_addr": "10.35.197.104", "first_switched": "2023-01-11t08:37:22.783z", "protocol": 6, "flowset_id": 257, "last_switched": "2023-01-11t08:37:22.783z", "version": 9, "dst_as": 0, "ip_dscp": 16, "ipv4_dst_addr": "10.46.1.138", "l4_src_port": 52114}
{"output_snmp": 9, "flow_seq_num": 48159, "src_tos": 64, "input_snmp": 1, "l4_dst_port": 22, "tcp_flags": 16, "in_bytes": 40, "in_pkts": 1, "ipv4_src_addr": "10.35.197.104", "first_switched": "2023-01-11t08:37:23.057z", "protocol": 6, "flowset_id": 256, "last_switched": "2023-01-11t08:37:23.057z", "version": 9, "dst_as": 0, "ip_dscp": 16, "ipv4_dst_addr": "10.46.1.138", "l4_src_port": 52114}

Output

{"output_snmp":[9,2],"ip_dscp":16,"dst_as":0,"in_pkts":1,"src_tos":64,"ipv4_dst_addr":"10.46.1.138","first_switched":["2023-01-11t08:37:23.057z","2023-01-11t08:37:22.783z"],"flowset_id":[256,257],"l4_src_port":52114,"version":9,"flow_seq_num":[48159,700710],"ipv4_src_addr":"10.35.197.104","in_bytes":40,"protocol":6,"input_snmp":[1,10],"tcp_flags":16,"last_switched":["2023-01-11t08:37:23.057z","2023-01-11t08:37:22.783z"],"l4_dst_port":22}

Describe alternatives you've considered (Optional)
The put_all aggregate action keeps values from the last event thus losing information.

Additional context
The use case is to stitch different netflow logs into one.

Start by locating the aggregate processor and the existing put_all action, then trace how action configuration and field values are handled. Use the supplied pipeline and input/output examples as the behavioral reference; done means a merge_all action can preserve configured fields as merged values while retaining other aggregate behavior.