docs(data_table): simplify the example docstring summary line

Use "A sample data table block." to match the sibling examples'
trailing docstring convention (e.g. "A simple header block.").

Co-Authored-By: Claude <svc-devxp-claude@slack-corp.com>

Author: zimeg

block-kit/src/blocks/data_table.py

@@ -12,7 +12,7 @@ def example01() -> DataTableBlock:
     Displays rich tables that support pagination, sorting, filtering, and interactivity.
     https://docs.slack.dev/reference/block-kit/blocks/data-table-block/
 
-    A data table of departments with raw text and rich text cells.
+    A sample data table block.
     """
     block = DataTableBlock(
         caption="A Fabulous Table",