vendor: Update vendored sources to duckdb/duckdb@20ae352

Fix sign-compare compilation warning (duckdb/duckdb#15672)
Fix Python dictionary key is repeated (duckdb/duckdb#15663)

Author: krlmlr

src/duckdb/src/common/types/varint.cpp

@@ -34,7 +34,7 @@ void Varint::Verify(const string_t &input) {
 	//  No bytes between 4 and end can be 0, unless total size == 4
 	if (varint_bytes > 4) {
 		if (is_negative) {
-			if (~varint_ptr[3] == 0) {
+			if (static_cast<data_t>(~varint_ptr[3]) == 0) {
 				throw InternalException("Invalid top data bytes set to 0 for VARINT values");
 			}
 		} else {

src/duckdb/src/function/table/version/pragma_version.cpp

@@ -1,5 +1,5 @@
 #ifndef DUCKDB_PATCH_VERSION
-#define DUCKDB_PATCH_VERSION "4-dev4492"
+#define DUCKDB_PATCH_VERSION "4-dev4496"
 #endif
 #ifndef DUCKDB_MINOR_VERSION
 #define DUCKDB_MINOR_VERSION 1
@@ -8,10 +8,10 @@
 #define DUCKDB_MAJOR_VERSION 1
 #endif
 #ifndef DUCKDB_VERSION
-#define DUCKDB_VERSION "v1.1.4-dev4492"
+#define DUCKDB_VERSION "v1.1.4-dev4496"
 #endif
 #ifndef DUCKDB_SOURCE_ID
-#define DUCKDB_SOURCE_ID "89bcc3e2ce"
+#define DUCKDB_SOURCE_ID "20ae352efc"
 #endif
 #include "duckdb/function/table/system_functions.hpp"
 #include "duckdb/main/database.hpp"