[BGP-IPv6] Use metrics instead of weights for IPv6 routes

nmstate does not support ECPM with IPv6:
NmstateError: NotSupportedError: IPv6 ECMP route with weight is not supported yet

Author: eduolivares

examples/dt/bgp_dt04_ipv6/control-plane/networking/nncp/values.yaml

@@ -27,11 +27,11 @@ data:
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:64:0:9"
           next-hop-interface: enp8s0
-          weight: 200
+          metric: 200
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:65:0:9"
           next-hop-interface: enp9s0
-          weight: 200
+          metric: 201
   node_4:
     name: worker-1
     internalapi_ip: "2620:cf:cf:bbbb::11"
@@ -51,11 +51,11 @@ data:
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:64:1:9"
           next-hop-interface: enp8s0
-          weight: 200
+          metric: 200
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:65:1:9"
           next-hop-interface: enp9s0
-          weight: 200
+          metric: 201
   node_5:
     name: worker-2
     internalapi_ip: "2620:cf:cf:bbbb::12"
@@ -75,11 +75,11 @@ data:
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:64:2:9"
           next-hop-interface: enp8s0
-          weight: 200
+          metric: 200
         - destination: f00d:f00d:f00d:f00d:99:99:0:0/96
           next-hop-address: "2620:cf::100:65:2:9"
           next-hop-interface: enp9s0
-          weight: 200
+          metric: 201
   node_6:
     name: worker-3
     node_name: worker-3
@@ -489,11 +489,11 @@ data:
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:64:0:9"
               next-hop-interface: enp8s0
-              weight: 200
+              metric: 200
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:65:0:9"
               next-hop-interface: enp9s0
-              weight: 200
+              metric: 201
             - destination: "2620:cf:cf:aaaa::0/64"
               next-hop-address: "2620:cf:cf:aaad::1"
               next-hop-interface: enp7s0
@@ -515,11 +515,11 @@ data:
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:64:1:9"
               next-hop-interface: enp8s0
-              weight: 200
+              metric: 200
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:65:1:9"
               next-hop-interface: enp9s0
-              weight: 200
+              metric: 201
             - destination: "2620:cf:cf:aaaa::0/64"
               next-hop-address: "2620:cf:cf:aaad::1"
               next-hop-interface: enp7s0
@@ -541,11 +541,11 @@ data:
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:64:2:9"
               next-hop-interface: enp8s0
-              weight: 200
+              metric: 200
             - destination: "f00d:f00d:f00d:f00d:99:99:0:0/96"
               next-hop-address: "2620:cf::100:65:2:9"
               next-hop-interface: enp9s0
-              weight: 200
+              metric: 201
             - destination: "2620:cf:cf:aaaa::0/64"
               next-hop-address: "2620:cf:cf:aaad::1"
               next-hop-interface: enp7s0