[ci] removes strategy to use toolchain from file

Author: wookietreiber

.github/workflows/rust.yml

@@ -28,25 +28,14 @@ env:
 jobs:
 
   test:
-    name: ubuntu-${{ matrix.toolchain }}
+    name: test
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        toolchain: [stable, beta, nightly]
-
     steps:
 
       - name: checkout
         uses: actions/checkout@v5
 
-      - name: set up rust toolchain
-        uses: actions-rs/toolchain@v1
-        with:
-          profile: minimal
-          toolchain: ${{ matrix.toolchain }}
-          components: clippy, rustfmt
-
       - name: cargo check
         uses: actions-rs/cargo@v1
         with: