Pin Rust version used on CI

Author: Kobzol

.github/workflows/main.yml

@@ -17,8 +17,8 @@ jobs:
       - name: Install Rust Stable
         run: |
           rustc -vV
-          rustup update stable
-          rustup default stable
+          rustup toolchain install 1.85.0
+          rustup default 1.85.0
           rustc -vV
 
       - uses: Swatinem/rust-cache@9d47c6ad4b02e050fd481d890b2ea34778fd09d6