gh-40893: Updated extension installation instructions
    
FIX #40876
Updated the documentation reference in doc/en/installation/launching.rst
(line 316).
Previously, it mentioned an extension named "Remote - WSL", which no
longer exists in the Visual Studio Code Marketplace (as of 2025/09).

Changes
Replaced "Remote - WSL" with "WSL" in the documentation.
    
URL: #40893
Reported by: Veer Mani Tripathi
Reviewer(s): Tobias Diez

Author: Release Manager

src/doc/en/installation/launching.rst

@@ -313,7 +313,7 @@ Here are steps to use SageMath in a Jupyter notebook in VS Code:
 
 * Click the "Extension" icon on the left (or press :kbd:`Ctrl` +
   :kbd:`Shift` + :kbd:`X`) to open a list of extensions. Install the
-  "Remote - WSL" and "Jupyter" extensions.
+  "WSL" and "Jupyter" extensions.
 
 * In the command palette (:kbd:`Ctrl` + :kbd:`Shift` + :kbd:`P`),
   enter "Remote-WSL: New Window", and hit :kbd:`Enter`.