[CI] quotes again

Author: MikailBag

.github/workflows/rust.yml

@@ -78,7 +78,7 @@ jobs:
         run: |
           sudo ./out/minion-tests --trace
       - name: Run tests (Windows)
-        if: matrix.os == "windows-2019"
+        if: matrix.os == 'windows-2019'
         run: |
           ./out.minion-tests.exe
         timeout-minutes: 3