make the actions actually install the version of rust for the tests r…

…ather than using the one packaged with the docker container

.github/workflows/rust.yml

@@ -107,6 +107,9 @@ jobs:
         git checkout -f $GITHUB_SHA
         git clean -fd
 
+    - name: Install Rust stable
+      uses: actions-rust-lang/setup-rust-toolchain@v1
+
     - name: Build
       uses: actions-rs/cargo@v1
       with:
@@ -159,6 +162,9 @@ jobs:
         git checkout -f $GITHUB_SHA
         git clean -fd
 
+    - name: Install Rust stable
+      uses: actions-rust-lang/setup-rust-toolchain@v1
+
     - name: Install calyx-py, MrXL, and queues
       working-directory: /home/calyx
       run: |
@@ -226,6 +232,9 @@ jobs:
         git checkout -f $GITHUB_SHA
         git clean -fd
 
+    - name: Install Rust stable
+      uses: actions-rust-lang/setup-rust-toolchain@v1
+
     - name: Build
       uses: actions-rs/cargo@v1
       with: