Add Wrapped MATIC to WETH9 addresses

[georgeroman]

This will result in consistent handling of the wrapped native currency on Polygon which uses MATIC instead of ETH:

sdk-core/src/entities/weth9.ts

Line 6 in be6b14f

export const WETH9: { [chainId: number]: Token } = {

[Florian-S-A-W]

@georgeroman I agree that this makes sense. I created a pull request to resolve this.

[ashutosh887]

I would like to work on this @Florian-S-A-W @georgeroman