[ja] Updated TTLAfterFinished feature reference

Author: Arhell

content/ja/docs/reference/command-line-tools-reference/feature-gates.md

@@ -136,7 +136,8 @@ content_type: concept
 | `TokenRequest` | `true` | Beta | 1.12 | |
 | `TokenRequestProjection` | `false` | Alpha | 1.11 | 1.11 |
 | `TokenRequestProjection` | `true` | Beta | 1.12 | |
-| `TTLAfterFinished` | `false` | Alpha | 1.12 | |
+| `TTLAfterFinished` | `false` | Alpha | 1.12 | 1.20 |
+| `TTLAfterFinished` | `true` | Beta | 1.21 | |
 | `TopologyManager` | `false` | Alpha | 1.16 | 1.17 |
 | `TopologyManager` | `true` | Beta | 1.18 | |
 | `ValidateProxyRedirects` | `false` | Alpha | 1.12 | 1.13 |