remove nightly

Author: askuric

.github/workflows/rust.yml

@@ -43,6 +43,6 @@ jobs:
         run: ETHERCAT_PATH=$(pwd)/ethercat-hg RUST_BACKTRACE=full cargo build --release
 
       - name: Build Docs
-        run: ETHERCAT_PATH=$(pwd)/ethercat-hg RUSTDOCFLAGS="--enable-index-page -Zunstable-options" cargo +nightly doc --no-deps --target-dir docs/api --workspace --lib
+        run: ETHERCAT_PATH=$(pwd)/ethercat-hg RUSTDOCFLAGS="--enable-index-page -Zunstable-options" cargo doc --no-deps --target-dir docs/api --workspace --lib