cloud: fix sla link (#1042)

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Author: michaellzc

docs/cloud/index.mdx

@@ -112,7 +112,7 @@ For unsupported private connectivity methods, Sourcegraph offers connectivity vi
 ### Health monitoring, support, and SLAs
 
 - Instance performance and health [monitored](/admin/observability/) by our team's on-call engineers.
-- [Support and SLAs](../sla/index.mdx).
+- [Support and SLAs](../sla/).
 
 ### Backup and restore