add yarn

Dockerfile

@@ -4,6 +4,7 @@ RUN apt update && \
 	apt -y install curl wget git git-lfs vim sudo iftop iotop build-essential p7zip-full xclip astyle tcpdump rsync htop locales mtr dnsutils net-tools traceroute tar unzip iperf iperf3 nmap mosh subversion nfs-common fish haveged python3-setuptools python3-dev python3-pip zstd mono-complete default-jdk openssh-client python-is-python3 jq && \
 	pip3 install -U pip && \
 	pip install -U awscli ansible==2.9.6 jinja2==3.0.0 && \
+	npm install -g yarn && \
 	rm -rf /var/tmp/* /tmp/* /var/lib/apt/lists/*
 
 ENTRYPOINT [ "/usr/bin/env" ]