Update README.md, Security Architecture URL 404 (#1107)

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README.md

@@ -59,7 +59,7 @@ Download native binaries of Cryptomator on [cryptomator.org](https://cryptomator
 
 ### Security Architecture
 
-For more information on the security details visit [cryptomator.org](https://cryptomator.org/architecture/).
+For more information on the security details visit [cryptomator.org](https://docs.cryptomator.org/en/latest/security/architecture/).
 
 ## Building