Migrate Mantle Payment Subgraph to 0xGraph

[MantisClone]

Problem

Our current Mantle subgraph deployments are on Graph Nodes that may choose to drop our subgraphs at any time.

• The testnet is on Mantle's old graph node
• The mainnet subgraph is on FuxionX's graph node.

Mantle has contracted Ormi Labs to host subgraphs for the Mantle ecosystem.

• https://www.mantle.xyz/blog/developers/subgraph-indexing-with-ormis-0xgraph
• https://docs.ormi.xyz/mantle-subgraphs/

Solution

Migrate the payment-subgraph on Mantle and Mantle Testnet to the Ormi graph nodes.

Definition of Done

• Deploy manually chore: migrate Mantle to 0xGraph #101 (comment)
• Update deployment Github Action - moved to Automate payment subgraph deployment to the Decentralized Network, Alchemy, and 0xGraph (Mantle) #63
• Update Request Network SDK chore: Update Mantle Payments Subgraph URL requestNetwork#1450
• Inform FusionX that when we're no longer using their Graph Node - @MantisClone sent them a message on Telegram ✅

[MantisClone]

I removed Mantle Testnet from the scope of this task because Mantle Testnet was L2 on top of Goerli which has ceased operation.

The new testnet is called Mantle Sepolia, but our smart contracts are not deployed on Mantle Sepolia.