Correct Windows installer links for 3.11.0 and 4.0.0

As of Daffodil 3.11.0, the Windows installer helper binaries switched
from an .msi to an .exe extension. But the release pages still
incorrectly reference the old .msi extension. This fixes that to use the
correct extension so release download links work correctly.

Author: stevedlawrence

site/_releases/3.11.0.md

@@ -12,7 +12,7 @@ source-dist:
 binary-dist:
  - "apache-daffodil-3.11.0-bin.tgz"
  - "apache-daffodil-3.11.0-bin.zip"
- - "apache-daffodil-3.11.0-bin.msi"
+ - "apache-daffodil-3.11.0-bin.exe"
  - "apache-daffodil-3.11.0-1.noarch.rpm"
 
 scala-version: 2.13

site/_releases/4.0.0.md

@@ -12,7 +12,7 @@ source-dist:
 binary-dist:
  - "apache-daffodil-4.0.0-bin.tgz"
  - "apache-daffodil-4.0.0-bin.zip"
- - "apache-daffodil-4.0.0-bin.msi"
+ - "apache-daffodil-4.0.0-bin.exe"
  - "apache-daffodil-4.0.0-1.noarch.rpm"
 
 scala-version: 3