Add RadiumBlock bootnodes to Coretime Polkadot Chain spec (#5967)

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# Description

Please consider adding RadiumBlock bootnodes to Coretime Polkadot Chain
spec

## Integration

*In depth notes about how this PR should be integrated by downstream
projects. This part is mandatory, and should be
reviewed by reviewers, if the PR does NOT have the `R0-Silent` label. In
case of a `R0-Silent`, it can be ignored.*

## Review Notes

*In depth notes about the **implementation** details of your PR. This
should be the main guide for reviewers to
understand your appro...

cumulus/parachains/chain-specs/coretime-polkadot.json

@@ -10,7 +10,9 @@
     "/dns4/coretime-polkadot.boot.stake.plus/tcp/30332/wss/p2p/12D3KooWFJ2yBTKFKYwgKUjfY3F7XfaxHV8hY6fbJu5oMkpP7wZ9",
     "/dns4/coretime-polkadot.boot.stake.plus/tcp/31332/wss/p2p/12D3KooWCy5pToLafcQzPHn5kadxAftmF6Eh8ZJGPXhSeXSUDfjv",
     "/dns/coretime-polkadot-boot-ng.dwellir.com/tcp/443/wss/p2p/12D3KooWGpmytHjdthrkKgkXDZyKm9ABtJ2PtGk9NStJDG4pChy9",
-    "/dns/coretime-polkadot-boot-ng.dwellir.com/tcp/30361/p2p/12D3KooWGpmytHjdthrkKgkXDZyKm9ABtJ2PtGk9NStJDG4pChy9"
+    "/dns/coretime-polkadot-boot-ng.dwellir.com/tcp/30361/p2p/12D3KooWGpmytHjdthrkKgkXDZyKm9ABtJ2PtGk9NStJDG4pChy9",
+    "/dns/coretime-polkadot-bootnode.radiumblock.com/tcp/30333/p2p/12D3KooWFsQphSqvqjVyKcEdR1D7LPcXHqjmy6ASuJrTr5isk9JU",
+    "/dns/coretime-polkadot-bootnode.radiumblock.com/tcp/30336/wss/p2p/12D3KooWFsQphSqvqjVyKcEdR1D7LPcXHqjmy6ASuJrTr5isk9JU"
   ],
   "telemetryEndpoints": null,
   "protocolId": null,
@@ -91,4 +93,4 @@
       "childrenDefault": {}
     }
   }
-}
\ No newline at end of file
+}