Update docs/pluggable-discovery-specification.md

Co-authored-by: Luca Bianconi <[email protected]>

Author: cmaglie

Diff for: docs/pluggable-discovery-specification.md

@@ -148,7 +148,7 @@ Each port has:
   `SSH on 192.168.10.100`)
 - `protocol` is the protocol identifier (such as `serial` or `dfu` or `ssh`)
 - `protocolLabel` is the `protocol` in human readable form (for example `Serial port` or `DFU USB` or `Network (ssh)`)
-- `hardwareId` (optional) a string that uniquely identify a specific board sample (even among other boards of the same
+- `hardwareId` (optional) a string that uniquely identifies a specific board sample (even among other boards of the same
   model). Different ports with the same `hardwareId` must belong to the same board sample. The identifier should be
   sufficiently long to uniquely identify the board sample and reduce the probability of collisions. Good examples of
   `hardwareId` values are: Ethernet MAC Address, USB Serial Number, CPU-ID number, etc.