let-chains only stabilized in 1.88

Author: quietlychris

.github/workflows/rust.yml

@@ -23,7 +23,7 @@ jobs:
       fail-fast: false
       matrix:
         toolchain:
-          - nightly-2025-02-20 # Should line up with the `1.85-stable` release date
+          - nightly-2025-06-26 # Should line up with the `1.88-stable` release date
           - nightly
 
     steps: