Add toolchain input to dtolnay/rust-toolchain

Author: lorisleiva

.github/workflows/main.yml

@@ -10,6 +10,7 @@ env:
   DO_NOT_TRACK: '1'
   NODE_VERSION: 20
   SOLANA_VERSION: 2.1.9
+  RUST_TOOLCHAIN: '1.86.0'
 
 jobs:
   lint:
@@ -47,6 +48,7 @@ jobs:
       - name: Install Rust Toolchain and Components
         uses: dtolnay/rust-toolchain@master
         with:
+          toolchain: ${{ env.RUST_TOOLCHAIN }}
           components: clippy, rustfmt
 
       - name: Install Solana ${{ env.SOLANA_VERSION }}