fix(connector-besu): do not crash if ledger unreachable - send HTTP 503 #200

Job	Run time
check-ci-skip	5s
ghcr-besu-all-in-one	21s
ghcr-corda-all-in-one-flowdb	2m 18s
ghcr-example-carbon-accounting	56s
ghcr-fabric2-all-in-one	1m 34s
ghcr-daml-all-in-one	1m 1s
ghcr-keychain-vault-server	1m 28s
ghcr-example-supply-chain-app	46s
compute_changed_packages	0s
check-coverage	0s
build-dev	0s
DCI-Lint	0s
ActionLint	0s
cactus-cmd-api-server	0s
cactus-api-client	0s
cactus-common	0s
cactus-common-example-server	0s
cactus-core	0s
cactus-core-api	0s
cactus-test-tooling	0s
cactus-verifier-client	0s
ce-carbon-accounting-backend	0s
ce-carbon-accounting-business-logic-plugin	0s
ce-carbon-accounting-frontend	0s
ce-supply-chain-backend	0s
ce-supply-chain-business-logic-plugin	0s
ce-supply-chain-frontend	0s
copm-tests	0s
cp-bungee-hermes	0s
cp-consortium-manual	0s
cp-consortium-static	0s
cp-htlc-coordinator-besu	0s
cp-htlc-eth-besu	0s
cp-keychain-azure-kv	0s
cp-htlc-eth-besu-erc20	0s
cp-keychain-aws-sm	0s
cpk-memory	0s
cpk-google-sm	0s
cpk-memory-wasm	0s
cpk-vault	0s
cplc-ethereum	0s
cplc-iroha2	0s
cpl-connector-aries	0s
cpl-connector-besu	0s
cpl-connector-corda	0s
cpl-connector-polkadot	0s
cpl-connector-stellar	0s
cplc-xdai	0s
cplc-sawtooth	0s
cp-object-store-ipfs	0s
cpp-ethereum	0s
ct-api-client	0s
cpp-fabric	0s
ct-cmd-api-server	0s
ct-geth-ledger	0s
ctp-consortium-manual	0s
ctp-htlc-eth-besu	0s
ctp-ledger-connector-besu	0s
ctp-htlc-eth-besu-erc20	0s
ctp-ledger-connector-ethereum	0s
ghcr-connector-corda-server	0s
ghcr-dev-container-vscode	0s
plc-fabric-0	0s
yarn_codegen	0s
yarn_custom_checks	0s
yarn_lint	0s
yarn_tools_validate_bundle_names	0s
	8m 29s

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