[Packetbeat] Disable install/auto-update of npcap

[jamiehynds]

When we initially started shipping npcap with Packetbeat and Network Packet Capture integration, we deferred on implementing config options to disable installation of our bundled npcap version and auto-updating our npcap instance. We were unsure on the use cases for these options, so we intentionally didn't focus on them.

Thanks to this Discuss issue we have identified a case where Microsoft's Defender for Identity relies on npcap 1.0, but we keep up to date with npcap and now run 1.70. Without the option to disable install/auto-update of our bundled npcap, Defender for Identity will continue to display warnings (even though functionality isn't affected).

This issue is intended to capture other use cases and discuss how we implement these config options. Some prior discussions available here.

[elasticmachine]

Pinging @elastic/security-external-integrations (Team:Security-External Integrations)