Query schema fixes; add query validation middleware [ci drivers]

src/metabase/db/migrations.clj

src/metabase/mbql/normalize.clj

src/metabase/mbql/schema.clj

src/metabase/mbql/schema/helpers.clj

src/metabase/mbql/util.clj

src/metabase/models/query_execution.clj

src/metabase/query_processor.clj

src/metabase/query_processor/middleware/cache.clj

src/metabase/query_processor/middleware/results_metadata.clj

src/metabase/query_processor/middleware/validate.clj

test/metabase/driver/mysql_test.clj

test/metabase/mbql/normalize_test.clj

...base/query_processor/middleware/results_metadata_test.clj

test/metabase/query_processor_test/aggregation_test.clj

test/metabase/query_processor_test/nested_queries_test.clj

test/metabase/sync/analyze/query_results_test.clj