Issue #3395627 by svendecabooter, hdnag, Wim Leers, borisson_, catch,...

Issue #3395627 by svendecabooter, hdnag, Wim Leers, borisson_, catch, smustgrave: Add validation constraints to field.settings

core/modules/field/config/schema/field.schema.yml

@@ -3,10 +3,16 @@
 field.settings:
   type: config_object
   label: 'Field settings'
+  constraints:
+    FullyValidatable: ~
   mapping:
     purge_batch_size:
       type: integer
       label: 'Maximum number of field data records to purge'
+      constraints:
+        NotNull: []
+        Range:
+          min: 1
 
 field.storage.*.*:
   type: config_entity