ci: Set some environment variables

Author: taiki-e

.github/workflows/ci.yml

@@ -13,6 +13,15 @@ on:
     - cron: '0 1 * * *'
   workflow_dispatch:
 
+env:
+  CARGO_INCREMENTAL: 0
+  CARGO_NET_GIT_FETCH_WITH_CLI: true
+  CARGO_NET_RETRY: 10
+  CARGO_TERM_COLOR: always
+  RUST_BACKTRACE: 1
+  RUSTFLAGS: -D warnings
+  RUSTUP_MAX_RETRIES: 10
+
 defaults:
   run:
     shell: bash