Update `pyth-sdk-cw` to v1.2.1

[larry0x]

The latest version address a bug: pyth-network/pyth-crosschain#941

But Pyth team still hasn't published it to crates.io yet. We can import it by:

pyth-sdk-cw = { version = "1.2.1", git = "https://github.com/pyth-network/pyth-crosschain.git", rev = "4f41525" }