make change function in builder as pub(crate)

Author: ZENOTME

crates/iceberg/src/spec/table_metadata.rs

@@ -342,7 +342,7 @@ impl TableMetadataBuilder {
     }
 
     /// Changes uuid of table metadata.
-    pub fn assign_uuid(mut self, uuid: Uuid) -> Result<Self> {
+    pub(crate) fn assign_uuid(mut self, uuid: Uuid) -> Result<Self> {
         self.0.table_uuid = uuid;
         Ok(self)
     }