fix: Add missing Variant type to Delta Lake type mapping table

Delta Lake Variant type is mapped to Arrow Struct in the code
(delta_lake.rs map_delta_data_type_to_arrow_data_type) but was
missing from the type mapping table in the docs.

Author: claudespice

website/docs/components/data-connectors/delta-lake/index.md

@@ -181,6 +181,7 @@ The table below shows the Delta Lake data types supported, along with the type m
 | `Decimal`       | `Decimal128`                          |
 | `Array`         | `List`                                |
 | `Struct`        | `Struct`                              |
+| `Variant`       | `Struct`                              |
 | `Map`           | `Map`                                 |
 
 ## Limitations

website/versioned_docs/version-1.10.x/components/data-connectors/delta-lake.md

@@ -179,6 +179,7 @@ The table below shows the Delta Lake data types supported, along with the type m
 | `Decimal`       | `Decimal128`                          |
 | `Array`         | `List`                                |
 | `Struct`        | `Struct`                              |
+| `Variant`       | `Struct`                              |
 | `Map`           | `Map`                                 |
 
 ## Limitations

website/versioned_docs/version-1.11.x/components/data-connectors/delta-lake.md

@@ -179,6 +179,7 @@ The table below shows the Delta Lake data types supported, along with the type m
 | `Decimal`       | `Decimal128`                          |
 | `Array`         | `List`                                |
 | `Struct`        | `Struct`                              |
+| `Variant`       | `Struct`                              |
 | `Map`           | `Map`                                 |
 
 ## Limitations