when snapshots can't be found for version, pick a random version

Right now there are no v18 snapshots on xtz-shots, so it's not possible
to kickstart a node. This PR will pick the v17 snapshot instead.

utils/config-generator.py

@@ -772,11 +772,14 @@ def create_node_snapshot_config_json(history_mode):
         and s.get("chain_name") == network_name
     ]
     if octez_version:
-        matching_snapshots = [
+        version_matching_snapshots = [
             s
             for s in matching_snapshots
             if int(octez_version) == s.get("tezos_version").get("version").get("major")
         ]
+        if len(version_matching_snapshots):
+            # If we can't find snapshots of the right octez version, we just pick the most recent available.
+            matching_snapshots = version_matching_snapshots
     matching_snapshots = sorted(matching_snapshots, key=lambda s: s.get("block_height"))
 
     return matching_snapshots[-1] if len(matching_snapshots) else None