`Scanning blocks [0, 0]` with `GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBE`R set to > 0 and dataSource without startBlock

从 graph/src/blockchain/polling_block_stream.rs 的第 329-331 行附近开始，然后使用 docker-compose 设置，在将 GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBER 设置为大于 0 的值并使用不带 startBlock 的 dataSource 的情况下重现。跟踪起始区块的选择方式，并验证扫描从配置的 genesis 区块开始，而不是从区块 0 开始。

Do you want to request a feature or report a bug?

Bug

What is the current behavior?

Running the graph-node from the docker-compose file (v0.28.2) and have set the genesis block to 1 with GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBER.
I'm deploying a subgraph without a start block and i get this log:

Nov 25 15:11:26.939 INFO Scanning blocks [0, 0], range_size: 1, sgd: 1, subgraph_id: QmeR431sHevtNDUq8LgHTJms9KHYEvzE5pA9kyYgWdkerr, component: BlockStream
Nov 25 15:11:26.939 DEBG Requesting logs for blocks [0, 0], contract 0x8a7fa94487d0d0460550e5f3f80a663c39ac8b10, 2 events, sgd: 1, subgraph_id: QmeR431sHevtNDUq8LgHTJms9KHYEvzE5pA9kyYgWdkerr, component: BlockStream
Nov 25 15:11:27.159 DEBG Block stream produced a non-fatal error, error: Failed to infer hash for block 0, sgd: 1, subgraph_id: QmeR431sHevtNDUq8LgHTJms9KHYEvzE5pA9kyYgWdkerr, component: SubgraphInstanceManager

I'm not sure if I'm looking at the right place, but here https://github.com/graphprotocol/graph-node/blob/master/graph/src/blockchain/polling_block_stream.rs#L329-L331 it states that it should start from the genesin block if (i assume) a start block is not set in the subgraph.yaml file, but on the next line the genesis block seem to be hardcoded to 0 and ignores the block set with GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBER.

If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem.

Set GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBER to > 0 in the docker-compose file
Deploy a subgraph with a dataSource without a startBlock

What is the expected behavior?

It should start scanning from the genesis block set with GRAPH_ETHEREUM_GENESIS_BLOCK_NUMBER instead of always starting from block 0