[feat] Blobstream Contracts Integration Tests

[b-j-roberts]

Create integration tests (scripts) for the Blobstream contract(s) by doing the following :

• Launch a Katana node
• Declare & Deploy the BlobstreamX contract ( & dependencies such as the gateway ) to the Katana node
• Make calls to public functions on BlobstreamX contract & check state updates are correct

Possibly use mock implementations where needed.

References

https://github.com/keep-starknet-strange/blobstream-starknet/blob/main/src/lib.cairo