fix: replace immutably with persistently in HIP-1137 blog

Signed-off-by: Mounil Kanakhara <mounilkankhara@gmail.com>

Author: Mounil2005

content/posts/hip-1137.md

@@ -45,7 +45,7 @@ Each endpoint may provide additional information specific to the endpoint servic
 
 **Consensus Node Association**: Consensus node operators can associate registered nodes they operate via the `associated_registered_nodes` list, enabling clients to find additional infrastructure associated with existing consensus nodes.
 
-**On-Chain Persistence**: All node information is stored immutably in the ledger state, making it authoritative and universally accessible to all network participants.
+**On-Chain Persistence**: All node information is stored persistently in the ledger state, making it authoritative and universally accessible to all network participants.
 
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