ci: exclude Windows / Beta Rust from CI (#285)

Signed-off-by: Spencer Wilson <[email protected]>

Author: SWilson4

.github/workflows/ci.yml

@@ -21,6 +21,8 @@ jobs:
         exclude:
           - os: windows-latest
             rust: nightly
+          - os: windows-latest
+            rust: beta
     env:
       # 20 MiB stack
       RUST_MIN_STACK: 20971520