vendor: Update vendored sources to duckdb/duckdb@a0b525c

fix passing a null path to the C API instance cache (duckdb/duckdb#16474)
[Python Dev] Make `pandas` not required in a couple places, check if it's installed in others (duckdb/duckdb#16414)

Author: krlmlr

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

@@ -1,5 +1,5 @@
 #ifndef DUCKDB_PATCH_VERSION
-#define DUCKDB_PATCH_VERSION "1-dev214"
+#define DUCKDB_PATCH_VERSION "1-dev221"
 #endif
 #ifndef DUCKDB_MINOR_VERSION
 #define DUCKDB_MINOR_VERSION 2
@@ -8,10 +8,10 @@
 #define DUCKDB_MAJOR_VERSION 1
 #endif
 #ifndef DUCKDB_VERSION
-#define DUCKDB_VERSION "v1.2.1-dev214"
+#define DUCKDB_VERSION "v1.2.1-dev221"
 #endif
 #ifndef DUCKDB_SOURCE_ID
-#define DUCKDB_SOURCE_ID "318e783c48"
+#define DUCKDB_SOURCE_ID "a0b525cb6d"
 #endif
 #include "duckdb/function/table/system_functions.hpp"
 #include "duckdb/main/database.hpp"

src/duckdb/src/main/capi/duckdb-c.cpp

@@ -35,7 +35,11 @@ duckdb_state duckdb_open_internal(DBInstanceCacheWrapper *cache, const char *pat
 		}
 
 		if (cache) {
-			wrapper->database = cache->instance_cache->GetOrCreateInstance(path, *db_config, true);
+			duckdb::string path_str;
+			if (path) {
+				path_str = path;
+			}
+			wrapper->database = cache->instance_cache->GetOrCreateInstance(path_str, *db_config, true);
 		} else {
 			wrapper->database = duckdb::make_shared_ptr<DuckDB>(path, db_config);
 		}