Followup to I188ce86d82616a071436f52f831253a16aa09e43

only set networks to 'none' in server create if server was not
requested to be validatable.

Closes-Issue: PRODX-47142
Change-Id: Ic39e4a54bd2bf644b6fe318eff143aa525e94409
diff --git a/tempest/api/volume/base.py b/tempest/api/volume/base.py
index b93ade5..3d82c8f 100644
--- a/tempest/api/volume/base.py
+++ b/tempest/api/volume/base.py
@@ -269,8 +269,11 @@
         tenant_network = self.get_tenant_network()
 
         # Since microversion v2.37 'networks' field is required
-        if self.compute_request_microversion >= '2.37' and 'networks'\
-                not in kwargs:
+        if (
+            self.compute_request_microversion >= '2.37' and
+            'networks' not in kwargs and
+            not kwargs.get("validatable", False)
+        ):
             kwargs['networks'] = 'none'
 
         body, _ = compute.create_test_server(