storage-node: use consistent debug prefix in discovery module

storage-node/packages/discovery/discover.js

@@ -1,5 +1,5 @@
 const axios = require('axios')
-const debug = require('debug')('discovery::discover')
+const debug = require('debug')('joystream:discovery:discover')
 const stripEndingSlash = require('@joystream/util/stripEndingSlash')
 
 const ipfs = require('ipfs-http-client')('localhost', '5001', { protocol: 'http' })

storage-node/packages/discovery/publish.js

@@ -1,7 +1,7 @@
 const ipfsClient = require('ipfs-http-client')
 const ipfs = ipfsClient('localhost', '5001', { protocol: 'http' })
 
-const debug = require('debug')('discovery::publish')
+const debug = require('debug')('joystream:discovery:publish')
 
 const PUBLISH_KEY = 'self' // 'services'