add an entry for Slack Your REST Client with a couple of Serde Tricks

Author: ifsheldon

draft/2025-02-19-this-week-in-rust.md

@@ -38,6 +38,7 @@ and just ask the editors to select the category.
 ### Project/Tooling Updates
 
 - [Towards Practical Formal Verification for a General-Purpose OS in Rust](https://asterinas.github.io/2025/02/13/towards-practical-formal-verification-for-a-general-purpose-os-in-rust.html)
+- [Slack Your REST Client with a couple of Serde Tricks](https://ideas.reify.ing/en/blog/rest-client-slack/)
 
 ### Observations/Thoughts