minor #9303 Mentioned the new "box" console style (javiereguiluz)

This PR was merged into the master branch.

Discussion
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Mentioned the new "box" console style

This fixes #9008.

Commits
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b9806ba Mentioned the new "box" console style

Author: javiereguiluz

components/console/helpers/table.rst

@@ -143,6 +143,27 @@ which outputs:
       80-902734-1-6   And Then There Were None   Agatha Christie
      =============== ========================== ==================
 
+You can also set the style to ``box``::
+
+    $table->setStyle('box');
+    $table->render();
+
+which outputs:
+
+.. code-block:: text
+
+    ┼───────────────┼──────────────────────────┼──────────────────┼
+    │ ISBN          │ Title                    │ Author           │
+    ┼───────────────┼──────────────────────────┼──────────────────┼
+    │ 99921-58-10-7 │ Divine Comedy            │ Dante Alighieri  │
+    │ 9971-5-0210-0 │ A Tale of Two Cities     │ Charles Dickens  │
+    │ 960-425-059-0 │ The Lord of the Rings    │ J. R. R. Tolkien │
+    │ 80-902734-1-6 │ And Then There Were None │ Agatha Christie  │
+    ┼───────────────┼──────────────────────────┼──────────────────┼
+
+.. versionadded:: 4.1
+    The ``box`` style was introduced in Symfony 4.1.
+
 If the built-in styles do not fit your need, define your own::
 
     use Symfony\Component\Console\Helper\TableStyle;