Disable Uniq/Distinct by default. Enable in tests

commit_hash:39033d97d7639a4749a6955577df43aba47bcef0

Author: rvu1024

yql/essentials/cfg/tests/gateways.conf

@@ -145,6 +145,10 @@ YqlCore {
         Name: "OptimizerFlags"
         Args: ["FieldSubsetEnableMultiusage"]
     }
+    Flags {
+        Name: "EnableConstraintCheck"
+        Args: ["Distinct","Unique"]
+    }
 }
 
 Dq {

yql/essentials/cfg/udf_test/gateways.conf

@@ -16,5 +16,9 @@ YqlCore {
     Flags {
         Name: "DisableYsonCastToString"
     }
+    Flags {
+        Name: "EnableConstraintCheck"
+        Args: ["Distinct","Unique"]
+    }
 }
 

yql/essentials/core/yql_type_annotation.cpp

@@ -40,6 +40,8 @@ bool TTypeAnnotationContext::DoInitialize(TExprContext& ctx) {
     Y_ENSURE(UserDataStorage);
     UserDataStorage->FillUserDataUrls();
 
+    DisableConstraintCheck.emplace(TUniqueConstraintNode::Name());
+    DisableConstraintCheck.emplace(TDistinctConstraintNode::Name());
 
     return true;
 }