fix:errors noticed when upgrading from older version

[chaitanyaprem]

After upgrade my existing nwaku node to latest master, node did not start and was restarting with below errros.

• Got following error eventhough my .env file is having the field RLN_RELAY_CRED_PASSWORD set. Error goes away after i export KEYSTORE_PASSWORD .

WARNING: The KEYSTORE_PASSWORD variable is not set. Defaulting to a blank string.

• Even after trying to export KEYSTORE_PASSWORD var, my node is still not coming up and keeps failing with below error.

ERR 2024-01-09 04:49:07.296+00:00 4/7 Mounting protocols failed topics="wakunode main" tid=1 file=wakunode2.nim:89 error="failed to mount waku RLN relay protocol: failed to mount WakuRlnRelay: exception in new WakuRlnRelay: could not parse the keystore: Error while reading keyfile for credentials: keyfile error: mac verification failed"

• Also updated to latest nwaku release version and added rest-admin to be enabled by default as it is useful

This PR fixes the above.

Thanks @gabrielmer for pointers to fix.

[chaitanyaprem]

Thanks so much!

I think we should probably also remove the single quotes fromregister_rln.sh, otherwise there will be incompatibility between the newer keystores generated and nwaku-compose

https://github.com/waku-org/nwaku-compose/blob/3a213909f990b8c6e24dadea1cee9b4cc39cc348/register_rln.sh#L23

Oh yes, somehow missed it. Will update it.