chore(zk_toolbox): update shared bridge url link to docs (#2754)

## What ❔

- Fixed docs link in zk_toolbox to shared bridge

## Why ❔

- Docs link in zk_toolbox to shared bridge was broken


## Checklist

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- [x] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [x] Tests for the changes have been added / updated.
- [x] Documentation comments have been added / updated.
- [x] Code has been formatted via `zk fmt` and `zk lint`.

zk_toolbox/README.md

@@ -37,7 +37,7 @@ Foundry is used for deploying smart contracts. Pass flags for Foundry integratio
 
 ZK Stack allows you to create a new ecosystem or connect to an existing one. An ecosystem includes components like the
 BridgeHub, shared bridges, and state transition managers.
-[Learn more](https://docs.zksync.io/zk-stack/components/shared-bridges.html).
+[Learn more](https://docs.zksync.io/zk-stack/components/shared-bridges).
 
 #### Global Config