zklogin: update prover url (#13843)

## Description 

Update prover url in doc

## Test Plan 

How did you test the new or updated feature?

---
If your changes are not user-facing and not a breaking change, you can
skip the following section. Otherwise, please indicate what changed, and
then add to the Release Notes section as highlighted during the release
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### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

doc/src/build/zk_login.md

@@ -217,7 +217,7 @@ Here's an example request and response for the Mysten Labs-maintained proving se
 Note that only valid JWT token authenticated with dev-only client ID is supported. If you wish to use the above endpoint for the ZK Proving Service, please contact us for whitelisting your registered client ID.
 
 ```bash
-curl -X POST http://prover-devnet.mystenlabs.com:8080/zkp -H 'Content-Type: application/json' -d '{"jwt":"$JWT_TOKEN","extendedEphemeralPublicKey":"84029355920633174015103288781128426107680789454168570548782290541079926444544","maxEpoch":"10","jwtRandomness":"100681567828351849884072155819400689117","salt":"248191903847969014646285995941615069143","keyClaimName":"sub"}'
+curl -X POST http://prover.mystenlabs.com:8080/v1 -H 'Content-Type: application/json' -d '{"jwt":"$JWT_TOKEN","extendedEphemeralPublicKey":"84029355920633174015103288781128426107680789454168570548782290541079926444544","maxEpoch":"10","jwtRandomness":"100681567828351849884072155819400689117","salt":"248191903847969014646285995941615069143","keyClaimName":"sub"}'
 
 Response: