Rename Remix packages/* folders in RR repo

[ryanflorence]

PR: #11704

Doing the folder rename later in the process so we can bring over git patches presumably easier since folder names won't have changed

packages/remix-dev -> packages/dev
packages/remix-express -> packages/express
packages/remix-node -> packages/node
packages/remix-serve -> packages/serve
packages/remix-server-runtime -> packages/server-runtime
packages/remix-testing -> packages/testing