Disable CI runs for stable / beta

Author: PixelDust22

.github/workflows/ci.yml

@@ -9,8 +9,8 @@ jobs:
     strategy:
       matrix:
         toolchain:
-          - stable
-          - beta
+#         - stable
+#         - beta
           - nightly
     steps:
       - uses: actions/checkout@v2

src/lib.rs

@@ -1,4 +1,5 @@
 //! Load MagicaVoxel .vox files into Rust
+#![feature(let_chains)]
 
 extern crate byteorder;
 #[cfg(test)]
@@ -216,8 +217,6 @@ pub mod placeholder {
 
 #[cfg(test)]
 mod tests {
-    use std::collections::HashMap;
-
     use super::*;
     use avow::vec;