tests/docker: fix sorting in package lists

This will make diffs in later patches clearer.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20210623142245.307776-7-berrange@redhat.com>
Message-Id: <20210709143005.1554-15-alex.bennee@linaro.org>

tests/docker/dockerfiles/ubuntu2004.docker

@@ -1,8 +1,10 @@
 FROM docker.io/library/ubuntu:20.04
-ENV PACKAGES flex bison \
+ENV PACKAGES \
+    bison \
     bsdmainutils \
     ccache \
     clang-10\
+    flex \
     gcc \
     gcovr \
     genisoimage \
@@ -65,8 +67,8 @@ ENV PACKAGES flex bison \
     sparse \
     tesseract-ocr \
     tesseract-ocr-eng \
-    xfslibs-dev\
-    vim
+    vim \
+    xfslibs-dev
 RUN apt-get update && \
     DEBIAN_FRONTEND=noninteractive apt-get -y install $PACKAGES
 RUN dpkg -l $PACKAGES | sort > /packages.txt