[netdata] ensure to update version on leader if there is any change (#8472)

This commit updates `RegisterNetdataData()` to ensure that versions
are updated if there is any change even if there is an error during
integration of new entries (e.g., running out of space in Network
Data, or failing to allocate new service ID).

src/core/thread/network_data_leader_ftd.cpp

@@ -712,11 +712,10 @@ void Leader::RegisterNetworkData(uint16_t aRloc16, const NetworkData &aNetworkDa
         }
     }
 
-    IncrementVersions(flags);
-
     DumpDebg("Register", GetBytes(), GetLength());
 
 exit:
+    IncrementVersions(flags);
 
     if (error != kErrorNone)
     {