Fix state leaf key removed query

[arijitAD]

The issue of storage key removal is fixed in #83 but the same issue exists for state key removal.

Query to fetch storage leaf node

https://github.com/vulcanize/ipld-eth-server/blob/8a105812c206067b6f1d266ed2daea2f9b2176c6/pkg/eth/ipld_retriever.go#L146-L160

Example:

SELECT storage_cids.cid,blocks.data,
    was_storage_removed(storage_path,block_number,'0x4d172383ff04943c44b55a043e56145db94caf7aed03487151f6182f1ce2ea78') 
    AS removed
FROM eth.storage_cids
         INNER JOIN eth.state_cids ON (storage_cids.state_id = state_cids.id)
         INNER JOIN eth.header_cids ON (state_cids.header_id = header_cids.id)
         INNER JOIN public.blocks ON (storage_cids.mh_key = blocks.key)
    WHERE state_leaf_key = '0x6114658a74d9cc9f7acf2c5cd696c3494d7c344d78bfec3add0d91ec4e8d1c45'
        AND storage_leaf_key = '0xb10e2d527612073b26eecdfd717e6a320cf44b4afac2b0732d9fcbe2b7fa0cf6'
        AND block_number <= (SELECT block_number
                       FROM eth.header_cids
                       WHERE block_hash = '0x4d172383ff04943c44b55a043e56145db94caf7aed03487151f6182f1ce2ea78')
        AND header_cids.id = (SELECTcanonical_header_id(block_number))
ORDER BY block_number DESC
LIMIT 1;

The above query will fetch the latest leaf node and this is passed on to was_storage_removed

This is the code before it was fixed.
https://github.com/vulcanize/ipld-eth-server/blob/8a105812c206067b6f1d266ed2daea2f9b2176c6/db/migrations/00014_create_stored_functions.sql#L4-L17

This will always return false as the height in was_storage_removed is the block_number passed , so height = block_number but block_number > height condition will evaluate to false.

This is fixed for the storage node in the master branch.
https://github.com/vulcanize/ipld-eth-server/blob/000c0ef066b530698a4d29f827a269c8fb4433b8/db/migrations/00014_create_stored_functions.sql#L11-L14

Added a fix for state node #98

[arijitAD]

Due to this incorrect query removed value was false and we were trying to decode nil value which lead to panic https://github.com/vulcanize/ipld-eth-server/blob/000c0ef066b530698a4d29f827a269c8fb4433b8/pkg/eth/ipld_retriever.go#L403-L409

[i-norden]

Fixed in #101