discv5+DNS: consolidating ENR information

[kaiserd]

Background

Currently nwaku builds two separate ENRs (in case discv5 is active) holding separate information.
One when initializing a waku node, and another one when initializing the discv5 subsystem.
The former might contain a DNS multiaddress, while the latter contains the UDP port necessary for discv5.

Goal / Motivation

Both ENR instances should contain the union of their respective current information.

• reduces confusion, because both ENR instances can be used interchangeably
• all information, including dns4 multiaddresses are discoverable via discv5
• sufficient to print a single ENR in the log (see fix(discv5): info print ENR containing discv5 udp port #913)

non-goals of this issue

For now, the discv5 subsystem holds a separate ENR instance. This issue does not propose consolidating both into a single ENR instance, as that would require more refactoring.
We might address that in the future though.

cc @jm-clius @richard-ramos

Acceptance criteria

• Wakunode2 and discv5 subsystem ENRs contain the same information
• successfully tested on experimental/local test fleet

[danisharora099]

This was also seen as a partial blocker during js-waku<>nwaku peer-exchange interop testing as multiaddrs was not received as part of the ENR.
It is intermittently being solved by making a PX query to the node for which discv5-bootstrap-node ENR is already added.

[jm-clius]

This could be a dependency for #1475

[rymnc]

This issue is addressed in #1512

[rymnc]

@jm-clius can we close this issue as #1512 has been merged?