automatic update of v1.3.0-rc.5 consensus spec URLs to v1.3.0

[tersec]

All Nim comment or markdown changes. No semantic changes.

Adjusted not to conflict with or overlap in changed files with #4832 #4843 #4844 #4846 #4847

nimbus-eth2$ git checkout beacon_chain/conf.nim beacon_chain/validators/validator_duties.nim docs/the_nimbus_book/src/options.md beacon_chain/nimbus_validator_client.nim beacon_chain/rpc/rest_constants.nim beacon_chain/rpc/rest_nimbus_api.nim beacon_chain/rpc/rest_utils.nim beacon_chain/spec/eth2_apis/{eth2_rest_serialization.nim,rest_common.nim,rest_nimbus_calls.nim} beacon_chain/validator_client/{api,common,doppelganger_service,fallback_service,fork_service}.nim beacon_chain/beacon_node.nim beacon_chain/consensus_object_pools/blob_quarantine.nim beacon_chain/consensus_object_pools/block_quarantine.nim beacon_chain/nimbus_beacon_node.nim beacon_chain/spec/datatypes/deneb.nim beacon_chain/sync/request_manager.nim  beacon_chain/nimbus_validator_client.nim  beacon_chain/rpc/rest_constants.nim beacon_chain/rpc/rest_nimbus_api.nim beacon_chain/rpc/rest_utils.nim  beacon_chain/spec/eth2_apis/eth2_rest_serialization.nim beacon_chain/spec/eth2_apis/rest_beacon_client.nim beacon_chain/spec/eth2_apis/rest_common.nim beacon_chain/spec/eth2_apis/rest_nimbus_calls.nim beacon_chain/spec/eth2_apis/rest_types.nim beacon_chain/validator_client/api.nim beacon_chain/validator_client/attestation_service.nim beacon_chain/validator_client/block_service.nim beacon_chain/validator_client/common.nim beacon_chain/validator_client/doppelganger_service.nim beacon_chain/validator_client/duties_service.nim beacon_chain/validator_client/fork_service.nim beacon_chain/validator_client/sync_committee_service.nim