attempt to fix yaml

Author: sunshowers

.github/workflows/ci.yml

@@ -39,7 +39,7 @@ jobs:
       matrix:
         os: [ ubuntu-latest, macos-latest, windows-latest ]
         # 1.60 is the MSRV
-        rust-version: [ 1.60, stable ]
+        rust-version: [ "1.60", stable ]
       fail-fast: false
     env:
       RUSTFLAGS: -D warnings