Update .gitea/workflows/rust.yml

Author: 鹳狸猿

.gitea/workflows/rust.yml

@@ -16,10 +16,6 @@ on: [push, pull_request]
 
 name: Continuous integration for Rust
 
-env:
-  RUSTUP_UPDATE_ROOT: "https://mirrors.cernet.edu.cn/rustup/rustup"
-  RUSTUP_DIST_SERVER: "https://mirrors.cernet.edu.cn/rustup"
-
 jobs:
   check:
     name: Check the code with cargo check