Bump version in README Docker commands to use latest (#148)

Author: tompntn

README.md

@@ -25,7 +25,7 @@ You can run the following command to open a shell in a linux docker container wi
 
 ```
 export PYTH_REPO=/path/to/host/pyth-client
-export IMAGE="docker.io/pythfoundation/pyth-client:devnet-v2.8.1"
+export IMAGE="docker.io/pythfoundation/pyth-client:devnet-v2.10.1"
 
 docker run -it \
   --volume "${HOME}:/home/pyth/home" \