[dartdev] minor update to the server template's description
[dartdev] minor update to the server template's description

Change-Id: If6e03feb0c54bfb914d3d20c27c1b63b9468c456
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/234441
Reviewed-by: Ben Konyi <67ffcaedcc3dc3d87dddb9627b72dd41756b31b1@google.com>
Commit-Queue: Ben Konyi <67ffcaedcc3dc3d87dddb9627b72dd41756b31b1@google.com>

dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk,dart-lang/sdk