Rust: Change rust/summary/summary-statistics to a diagnostic query, so that it gets run as a diagnmetric query for DCA.

Author: geoffw0

rust/ql/src/queries/summary/SummaryStats.ql

@@ -1,7 +1,7 @@
 /**
  * @name Summary Statistics
  * @description A table of summary statistics about a database.
- * @kind table
+ * @kind diagnostic
  * @id rust/summary/summary-statistics
  * @tags summary
  */