Update README.md

Author: NovaDev404

README.md

@@ -25,7 +25,7 @@ ProSign app source URL: https://prostore-ios.github.io/apps.json
 ---
 
 # To-Do
-- [ ] Implement certificate selection on the Signing page.
+- [x] Implement certificate selection on the Signing page.
 - [x] Resolve issue causing some page titles to not display correctly.
 - [x] Resolve color inconsistencies on the Certificates page
 - [ ] Display certificate status indicators: *Revoked*, *Signed*, or *Expiring Soon*.