docs(l1,l2): add rich accounts to docs (#5383)

**Motivation**

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**Description**

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Closes #issue_number

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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: ManuelBilbao

docs/SUMMARY.md

@@ -77,6 +77,7 @@
   - [Ethrex L2 as local development mode](./developers/l2/dev-mode.md)
   - [Integration tests](./developers/l2/integration-tests.md)
   - [Generate blobs for the state reconstruction test](./developers/l2/state-reconstruction-blobs.md)
+- [Rich Accounts](./developers/rich-accounts.md)
 - [Debugging solidity with ethrex](./vm/levm/debug.md)
 - [Re-execute Ethereum with ethrex](./ethrex_replay/ethrex_replay.md)
   - [FAQ](./ethrex_replay/faq.md)