Add smoke tests for subgraph examples

[Kalina-Todorova]

Problem

As a developer I can run a single command (such as hardhat test) in order to verify that the basic (ERC20, ERC721, Gravatar) examples run correctly against local-node, previewnet, testnet or mainnet.

The command would ideally execute the following:

1. start up graph node and local-node and verify that they have are running successfully
2. pass all required params to deploy script to avoid manual passing through cli
3. execute interaction scripts
4. handle awaits
5. verify that the synced values reflect what is expected

Solution

The initial tests should include the following scenarios:

1. Can index old events:

• Interact with contracts, emit events
• Deploy subgraph
• Wait for indexing
• Send GraphQL queries to the subgraph endpoint to check if data is correct

2. Can index new events:

• Interact with contracts and emit events
• Wait for indexing
• Send GraphQL queries and check if returned data is correct

Alternatives

No response