ci: use freebsd pkg installer to install yarn/npm (#325)

* ci: use freebsd pkg installer to install yarn

* ci: use freebsd pkg installer to install npm

.github/workflows/CI.yml

@@ -179,9 +179,7 @@ jobs:
           usesh: true
           mem: 3000
           prepare: |
-            pkg install -y -f curl node libnghttp2
-            curl -qL https://www.npmjs.com/install.sh | sh
-            npm install --location=global --ignore-scripts yarn
+            pkg install -y -f curl node libnghttp2 npm yarn
             curl https://sh.rustup.rs -sSf --output rustup.sh
             sh rustup.sh -y --profile minimal --default-toolchain beta
             export PATH="/usr/local/cargo/bin:$PATH"