Remove duplicate job

Author: JustForFun88

.github/workflows/rust.yml

@@ -73,9 +73,6 @@ jobs:
         - os: windows-latest
           target: x86_64-pc-windows-msvc
           channel: 1.64.0
-        - os: ubuntu-latest
-          target: x86_64-unknown-linux-gnu
-          channel: 1.64.0
         - os: ubuntu-latest
           target: x86_64-unknown-linux-gnu
           channel: beta