This inconsistency makes it hard when querying or aggregating metrics, one would have to account for both fields.
Here's the list:

1. path_name:

   • cosmos_relayer_client_expiration_seconds
   • cosmos_relayer_client_trusting_period_seconds

2. path:

   • cosmos_relayer_observed_packets
   • cosmos_relayer_relayed_packets
   • cosmos_relayer_tx_errors_total

I propose we change

• cosmos_relayer_observed_packets
• cosmos_relayer_relayed_packets
• cosmos_relayer_tx_errors_total

to path_name