feat(discv5): filter peer by capability

[chaitanyaprem]

Problem

Discv5 filtering doesn't follow the RFC and filter ENR caps. Refer https://github.com/waku-org/nwaku/issues/2179

Suggested solution

Add to the filtering a check for empty caps.

Follow the RFC https://rfc.vac.dev/spec/31/#usage-1

Acceptance criteria

• [x] Peers discovered with ENR missing the waku2 field or no capability set must be filtered out.

[chaitanyaprem]

Weekly Update

• achieved: added capacility in discv5 to filter out peers that do not have waku2 ENR field