[Test] Fix schema version

test/functional/cases/210_clickhouse/001_migration.robot

@@ -39,7 +39,7 @@ Migration
   Column should exist  rspamd  Symbols.Scores
   Column should exist  rspamd  Attachments.Digest
   Column should exist  rspamd  Symbols.Scores
-  Schema version should be  3
+  Schema version should be  4
 
 
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