Fix CI hangs and improve github actions scripts

scripts/build-docs.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+set -e
+
+cd docs
+
+npm ci
+npm run format:check
+npm run spell:check
+npm run build
+
+cd -

scripts/check.sh

@@ -20,7 +20,7 @@ else
     cargo fmt --all -- --check
 fi
 
-cargo install cargo-machete
+which cargo-machete || cargo install cargo-machete
 cargo machete --with-metadata
 
 echo "Running checks in frontend"