Label perforce as beta not experimental (#953)

Label perforce as beta not experimental

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Author: mmanela

docs/admin/permissions/index.mdx

@@ -63,7 +63,7 @@ Support for repository permissions accross different code hosts is different. Th
 | GitHub Enterprise | ✓ | ✓ | ✓ | 40k users, 200k repositories |
 | GitLab | ✓ | ✗ | ✓ | 40k users, 200k repositories |
 | GitLab Self-Managed | ✓ | ✗ | ✓ | 40k users, 200k repositories |
-| Perforce (Experimental) | Yes (with file-level permissions) | ✓ | ✓ | 10k users, 250k repositories |
+| Perforce (Beta) | Yes (with file-level permissions) | ✓ | ✓ | 10k users, 250k repositories |
 
 All the other code hosts only support [Explicit permissions API](/admin/permissions/api).