fix: Fix wrong ARCH.

Dockerfile

@@ -23,7 +23,7 @@ RUN ARCH=$(uname -m) && case $ARCH in aarch64) ARCH="arm64";; x86_64) ARCH="amd6
     curl -sLf https://storage.googleapis.com/kubernetes-release/release/v1.20.5/bin/linux/${ARCH}/kubectl > /usr/bin/kubectl && chmod +x /usr/bin/kubectl && \
     git clone --branch master --depth 1 https://github.com/ahmetb/kubectl-aliases /opt/kubectl-aliases && chmod -R 755 /opt/kubectl-aliases && \
     git clone --branch 0.21.0 --depth 1 https://github.com/junegunn/fzf /opt/fzf && chmod -R 755 /opt/fzf && /opt/fzf/install && ln -s /opt/fzf/bin/fzf /usr/local/bin/fzf && \
-    if [[ $ARCH == arm* ]]; then ARCH=arm64; else ARCH=x86_64; fi && echo $ARCH && \
+    ARCH=$(uname -m) && case $ARCH in aarch64) ARCH="arm64";; x86_64) ARCH="x86_64";; esac && echo "ARCH: " $ARCH && \
     cd /tmp/ && wget https://github.com/derailed/k9s/releases/download/v0.24.7/k9s_Linux_${ARCH}.tar.gz && tar -xvf k9s_Linux_${ARCH}.tar.gz && chmod +x k9s && mv k9s /usr/bin && \
     KUBECTX_VERSION=v0.9.3 && wget https://github.com/ahmetb/kubectx/releases/download/${KUBECTX_VERSION}/kubens_${KUBECTX_VERSION}_linux_${ARCH}.tar.gz && tar -xvf kubens_${KUBECTX_VERSION}_linux_${ARCH}.tar.gz && chmod +x kubens && mv kubens /usr/bin && \
     wget https://github.com/ahmetb/kubectx/releases/download/${KUBECTX_VERSION}/kubectx_${KUBECTX_VERSION}_linux_${ARCH}.tar.gz && tar -xvf kubectx_${KUBECTX_VERSION}_linux_${ARCH}.tar.gz && chmod +x kubectx && mv kubectx /usr/bin && \
@@ -44,4 +44,4 @@ ENV WELCOME_BANNER="Welcome to Web Kubectl, try kubectl --help."
 ENV KUBECTL_INSECURE_SKIP_TLS_VERIFY=true
 ENV GOTTY_OPTIONS="--port 8080 --permit-write --permit-arguments"
 
-CMD ["sh","/opt/webkubectl/start-webkubectl.sh"]
+CMD ["sh","/opt/webkubectl/start-webkubectl.sh"]