Replace dead beaconstate.info checkpoint-sync domains

- mainnet.beaconstate.info -> beaconstate.ethstaker.cc
- sepolia.beaconstate.info -> checkpoint-sync.sepolia.ethpandaops.io
- Preserve holesky.beaconstate.info and beaconstate-hoodi.chainsafe.io (alive)

Fixes CL container crash-loops on fresh starts due to dead DNS.

Generated by Mistral Vibe.
Co-Authored-By: Mistral Vibe <vibe@mistral.ai>

ethereum/reth/ethereum-mainnet-reth-pruned-trace--lighthouse.yml

@@ -118,7 +118,7 @@ services:
       - 3500
     entrypoint: [lighthouse, beacon_node]
     command:
-      - --checkpoint-sync-url=https://mainnet.beaconstate.info
+      - --checkpoint-sync-url=https://beaconstate.ethstaker.cc
       - --datadir=/data
       - --debug-level=info
       - --disable-log-timestamp