unhide config discovery option for network filters

[ramaraochavali]

#28407 implemented config discovery for network filters. This PR unhides it from api
Commit Message: unhide config discovery option for network filters
Additional Description: unhide config discovery option for network filters
Risk Level: N/A
Testing: N/A
Docs Changes: N/A
Release Notes: N/A
Platform Specific Features:
[Optional Runtime guard:]
[Optional Fixes #Issue]
[Optional Fixes commit #PR or SHA]
[Optional Deprecated:]
[Optional API Considerations:]

[repokitteh-read-only]

CC @envoyproxy/api-shepherds: Your approval is needed for changes made to (api/envoy/|docs/root/api-docs/).
envoyproxy/api-shepherds assignee is @adisuissa
CC @envoyproxy/api-watchers: FYI only for changes made to (api/envoy/|docs/root/api-docs/).

🐱

Caused by: #28507 was opened by ramaraochavali.

see: more, trace.

[adisuissa]

Thanks for following up on this!
Looking at this comment, I'm not sure if the API should be changed now or wait until at least some integration tests are added to validate that it works. @ohadvano @kyessenov WDYT?

[ohadvano]

Hi @ramaraochavali, that PR you mentioned only adjusts the interfaces to use config discovery but does not enable ECDS for network filters just yet. The follow up: #28477 adds implementation, integration test and adjusts API+docs. @adisuissa maybe you could replace Lizan as api reviewer as I see he's out?

[ramaraochavali]

Ah. I thought it is implemented already. Will close this.