feat(backup): change log level debug to trace

This is done to reduce the verbosity of the logs in debug mode as
the backup logic will log multiple statements for every operation
affecting channels or databases such as a swap.

lib/backup/Backup.ts

@@ -117,7 +117,7 @@ class Backup extends EventEmitter {
         this.logger.info(`Listening to ${currency} LND channel backups`);
 
         lndClient.on('channelBackup', (channelBackup) => {
-          this.logger.debug(`New ${lndClient.currency} channel backup`);
+          this.logger.trace(`New ${lndClient.currency} channel backup`);
           this.writeBackup(backupPath, channelBackup);
         });
         lndClient.on('channelBackupEnd', async () => {
@@ -169,7 +169,7 @@ class Backup extends EventEmitter {
         // Compare the MD5 hash of the current content of the file with hash of the content when
         // it was backed up the last time to ensure that the content of the file has changed
         if (hash !== previousDatabaseHash) {
-          this.logger.debug(`${client} database changed`);
+          this.logger.trace(`${client} database changed`);
 
           previousDatabaseHash = hash;
           this.writeBackup(backupPath, content);