[8.18](backport #42626) Fixing NPCAP install with agentbeat

[mergify]

For this to test properly we need snapshot build (find snapshot for windows in buildkite pipeline artifacts for agentbeat packaging)
For some reason locally built agentbeats do not have an issue.

How to test

spin up Window Server 2022 VM without npcap
use config packetbeat.yml

packetbeat.interfaces.poll_default_route: 1m
packetbeat.interfaces.internal_networks:
  - private

packetbeat.flows:
  timeout: 30s
  period: 10s


packetbeat.protocols:
- type: dhcpv4
  ports: [67, 68]

- type: dns
  ports: [53]

- type: http
  ports: [80, 8080, 8000, 5000, 8002]

- type: tls
  ports:
    - 443   # HTTPS
    - 993   # IMAPS
    - 995   # POP3S
    - 5223  # XMPP over SSL
    - 8443
    - 8883  # Secure MQTT
    - 9243  # Elasticsearch

- type: sip
  ports: [5060]

setup.template.settings:
  index.number_of_shards: 1

setup.kibana: 
output.elasticsearch:
  # Array of hosts to connect to.
  hosts: ["localhost:9200"]

  # Pipeline to route events to protocol pipelines.
  pipeline: "packetbeat-%{[agent.version]}-routing"


processors:
  - # Add forwarded to tags when processing data from a network tap or mirror.
    if.contains.tags: forwarded
    then:
      - drop_fields:
          fields: [host]
    else:
      - add_host_metadata: ~
  - add_cloud_metadata: ~
  - add_docker_metadata: ~
  - detect_mime_type:
      field: http.request.body.content
      target: http.request.mime_type
  - detect_mime_type:
      field: http.response.body.content
      target: http.response.mime_type

run agentbeat packetbeat run -c packetbeat.yml
no error should be present

Closes elastic/elastic-agent#6108

---

This is an automatic backport of pull request #42626 done by Mergify.

[mergify]

Cherry-pick of 6763697 has failed:

On branch mergify/bp/8.18/pr-42626
Your branch is up to date with 'origin/8.18'.

You are currently cherry-picking commit 67636970b.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   .buildkite/x-pack/pipeline.xpack.agentbeat.yml
	modified:   x-pack/agentbeat/magefile.go
	modified:   x-pack/packetbeat/scripts/mage/pcap.go

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   x-pack/packetbeat/magefile.go
	both modified:   x-pack/packetbeat/tests/system/app_run_agentbeat_test.go

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elasticmachine]

Pinging @elastic/elastic-agent-data-plane (Team:Elastic-Agent-Data-Plane)

[dliappis]

@michalpristas is this commented out on purpose?
I see the following failure which might be related: https://buildkite.com/elastic/beats-xpack-agentbeat/builds/7836#0195137e-6ead-45f3-8641-1919a716408b/122-130

[michalpristas]

yes this file is not here, i need to do some other backports and uncomment this

[michalpristas]

backports done, uncommented

[mergify]

This pull request is now in conflicts. Could you fix it? 🙏
To fixup this pull request, you can check out it locally. See documentation: https://help.github.com/articles/checking-out-pull-requests-locally/

git fetch upstream
git checkout -b mergify/bp/8.18/pr-42626 upstream/mergify/bp/8.18/pr-42626
git merge upstream/8.18
git push upstream mergify/bp/8.18/pr-42626

[dliappis]

LGTM, provided that CI becomes green