feat: Support single asset vault (#1979)

fixes #1921

---------

Co-authored-by: Sergey Kuznetsov <skuznetsov@ripple.com>
Co-authored-by: Ayaz Salikhov <mathbunnyru@users.noreply.github.com>

tests/unit/util/LedgerUtilsTests.cpp

@@ -57,6 +57,7 @@ TEST(LedgerUtilsTests, LedgerObjectTypeList)
         JS(permissioned_domain),
         JS(oracle),
         JS(credential),
+        JS(vault),
         JS(nunl),
         JS(delegate)
     };
@@ -92,6 +93,7 @@ TEST(LedgerUtilsTests, AccountOwnedTypeList)
         JS(mpt_issuance),
         JS(mptoken),
         JS(permissioned_domain),
+        JS(vault),
         JS(delegate)
     };