Update reference to Passkey code in README.md (#398)

Fixes #345

Changes in PR:
- non-related: Fix a broken link to Passkey Signer contract

The broken link for which the issue was created has already been fixed.

examples/4337-passkeys/README.md

@@ -1,6 +1,6 @@
 # Safe + 4337 + Passkeys example application
 
-This minimalistic example application demonstrates a Safe{Core} Smart Account deployment leveraging 4337 and Passkeys. It uses experimental and unaudited (at the moment of writing) contracts: [SafeSignerLaunchpad](https://github.com/safe-global/safe-modules/blob/main/modules/passkey/contracts/4337/SafeSignerLaunchpad.sol) and [SafeWebAuthnSigner](https://github.com/safe-global/safe-modules/blob/main/modules/passkey/contracts/SafeWebAuthnSigner.sol), which uses [FreshCryptoLib](https://github.com/rdubois-crypto/FreshCryptoLib/) under the hood.
+This minimalistic example application demonstrates a Safe{Core} Smart Account deployment leveraging 4337 and Passkeys. It uses experimental and unaudited (at the moment of writing) contracts: [SafeSignerLaunchpad](https://github.com/safe-global/safe-modules/blob/main/modules/passkey/contracts/4337/SafeSignerLaunchpad.sol) and [SafeWebAuthnSignerProxy](https://github.com/safe-global/safe-modules/blob/main/modules/passkey/contracts/SafeWebAuthnSignerProxy.sol), which uses [FreshCryptoLib](https://github.com/rdubois-crypto/FreshCryptoLib/) under the hood.
 
 ## Running the app