DevOps updates for after v0.32.0 release

[lightwalker-eth]

With the v0.32.0 release, ENSAdmin no longer needs RPC configurations and can instead just read from the connected ENSNode instance.

Subtasks

• Remove all RPC-related environment variable configurations from ENSAdmin in Vercel (all environment variables beginning with NEXT_PUBLIC_RPC_URL_...).
• Remove the "ENSAdmin" app from our Alchemy account.

[lightwalker-eth]

Confirmed as completed 👍