ci90

Author: Riateche

.github/workflows/ci-message-buffer.yml

@@ -19,6 +19,7 @@ jobs:
         uses: actions/checkout@v3
       - uses: actions-rust-lang/setup-rust-toolchain@v1
         with:
+          toolchain: 1.66.1
           cache-workspaces: "pythnet/message_buffer -> target"
       - name: Install Solana
         run: |