Disable Rust 2021 compat warnings (#37)

These should be handled when doing the upgrade, and still cause false positives in Post-2021 crates (such as zookeeper-operator).

Author: nightkr

template/.github/workflows/rust.yml

@@ -16,7 +16,7 @@ env:
  CARGO_TERM_COLOR: always
  CARGO_INCREMENTAL: '0'
  CARGO_PROFILE_DEV_DEBUG: '0'
- RUSTFLAGS: "-D warnings -W rust-2021-compatibility"
+ RUSTFLAGS: "-D warnings"
 
 jobs: