doc(CONTRIBUTING.md): fix link to project code of conduct on LDK website

Author: Anyitechs

Diff for: CONTRIBUTING.md

@@ -12,7 +12,7 @@ testing and risk-minimization. Any bug may cost users real money. That being
 said, we deeply welcome people contributing for the first time to an open source
 project or pick up Rust while contributing. Don't be shy, you'll learn.
 
-For the project Code of Conduct, see our [website](https://lightningdevkit.org/code_of_conduct).
+For the project Code of Conduct, see our [website](https://lightningdevkit.org/code-of-conduct/).
 
 Communication Channels
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