Update status

Author: czechboy0

Sources/Configuration/Documentation.docc/Proposals/SCO-0002.md

@@ -6,7 +6,7 @@ Remove the custom key decoder feature to fix a flaw and simplify the project
 
 - Proposal: SCO-0002
 - Author(s): [Honza Dvorsky](https://github.com/czechboy0)
-- Status: **Ready for Implementation**
+- Status: **Implemented (1.0.0-alpha.1)**
 - Issue: [apple/swift-configuration#70](https://github.com/apple/swift-configuration/issues/70)
 - Implementation:
     - [apple/swift-configuration#71](https://github.com/apple/swift-configuration/pull/71)