feat: use rust 2021 edition

Author: lherman-cs

.github/workflows/rust.yml

@@ -11,11 +11,11 @@ env:
 
 jobs:
   build:
-
     runs-on: ubuntu-latest
-
     steps:
     - uses: actions/checkout@v4
+      with:
+        submodules: 'recursive'
     - name: Build
       run: cargo build --verbose
     - name: Run tests

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "pulsebeam-server-lite"
 version = "0.1.0"
-edition = "2024"
+edition = "2021"
 
 [dependencies]
 axum = "0.8.1"