fixup

Author: davidtaylorhq

image/discourse_test/Dockerfile

@@ -23,7 +23,7 @@ RUN /tmp/install-chrome &&\
     apt update &&\
     apt install -y libgconf-2-4 libxss1 firefox-esr &&\
     cd /tmp && wget -q "https://download.mozilla.org/?product=firefox-latest-ssl&os=linux64&lang=en-US" -O firefox.tar.xz &&\
-    tar xjvf firefox.tar.xz && mv /tmp/firefox /opt/firefox-evergreen &&\
+    tar xJvf firefox.tar.xz && mv /tmp/firefox /opt/firefox-evergreen &&\
     apt clean &&\
     rm /tmp/firefox.tar.xz