Revert "Temporarily pin to SDK v9"

This reverts commit dc1cb2d.

Author: andrew-polk

CHANGELOG.md

@@ -27,7 +27,6 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - [SIL.Windows.Forms.Keyboarding] BREAKING CHANGE: Upgraded to L10nSharp v9. Any clients which also use L10nSharp must also upgrade to v9.
 - [SIL.Windows.Forms.Keyboarding] Add a reference to L10nSharp.Windows.Forms v9.
 - [SIL.Windows.Forms] BREAKING CHANGE: ToolStripExtensions.InitializeWithAvailableUILocales() removed the ILocalizationManager parameter.  This method no longer provides functionality to display the localization dialog box in response to the user clicking More.
-- Temporarily pinned SDK to v9 using global.json.
 
 ### Removed
 
@@ -45,7 +44,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 
 - [SIL.Windows.Forms] Made ContributorsListControl.GetCurrentContribution() return null in the case when a valid row is not selected.
-- [SIL.WritingSystems] Make the English names for Chinese (Simplified) and Chinese (Traditional) consistent regardless of differences in Windows CultureInfo
+- [SIL.WritingSystems] Make the English names for Chinese (Simplified) and Chinese (Traditional) consistent regardless of differences in Windows CultureInfo 
 
 ## [16.1.0] - 2025-07-18