Remove show external only flag

[jdewinne]

Get a network report showing detailed network activity for a specified network.

The report shows individual network events including source/destination IPs, ports, protocols,
pods, processes, and DNS queries. Reports must be enabled with 'replicated network update <network-id> --collect-report'.

Output formats:
  - Default: Full event details in JSON format
  - --summary: Aggregated statistics with top domains and destinations
  - --watch: Continuous stream of new events in JSON Lines format


Usage:
  replicated network report [network-id] [flags]

Example:
  # Get full network traffic report (external traffic only)
  replicated network report <network-id>

  # Get aggregated summary with statistics. Only available for networks that have been terminated.
  replicated network report <network-id> --summary

  # Watch for new network events in real-time
  replicated network report <network-id> --watch

Flags:
  -h, --help        help for report
      --id string   Network ID to get report for
      --summary     Get aggregated report summary with statistics instead of individual events
  -w, --watch       Watch for new network events in real-time (polls every 2 seconds)

Global Flags:
      --app string       The app slug or app id to use in all calls
      --debug            Enable debug output
      --profile string   The authentication profile to use for this command
      --token string     The API token to use to access your app in the Vendor API

[mikhailswift]

i wonder if we want to leave this flag added but hidden, so if vendors have this in their CI scripts it won't fail. optionally we can display a deprecated warning as well if the hidden flag is supplied