fix: error during deserialization of "INVERTED" index type

rust/lancedb/src/index.rs

@@ -134,6 +134,7 @@ impl std::fmt::Display for IndexType {
             Self::Bitmap => write!(f, "BITMAP"),
             Self::LabelList => write!(f, "LABEL_LIST"),
             Self::FTS => write!(f, "FTS"),
+            Self::INVERTED => write!(f, "FTS"),
         }
     }
 }