fix: pulumi install script no longer supports empty --version

Author: Ishirui

Dockerfile

@@ -104,7 +104,7 @@ RUN curl --retry 10 -fsSLo /tmp/helm.tgz https://get.helm.sh/helm-v${HELM_VERSIO
 ARG PULUMI_VERSION
 
 # Install the Pulumi SDK, including the CLI and language runtimes.
-RUN curl --retry 10 -fsSL https://get.pulumi.com/ | bash -s -- --version $PULUMI_VERSION && \
+RUN curl --retry 10 -fsSL https://get.pulumi.com/ | bash -s && \
   mv ~/.pulumi/bin/* /usr/bin
 
 # Install Pulumi plugins