Install lxml using apt.

orchestra/bin/orchestra-admin

@@ -116,20 +116,17 @@ function install_requirements () {
         update-locale LANG=en_US.UTF-8
     fi
 
-    # lxml: libxml2-dev, libxslt1-dev, zlib1g-dev
     APT="bind9utils \
          ca-certificates \
          gettext \
          libcrack2-dev \
-         libxml2-dev \
-         libxslt1-dev \
          python3 \
          python3-pip \
          python3-dev \
+         python3-lxml \
          ssh-client \
          wget \
-         xvfb \
-         zlib1g-dev"
+         xvfb"
     if $testing; then
         APT="${APT} \
             git \
@@ -151,8 +148,7 @@ function install_requirements () {
 
     # cracklib and lxml are excluded on the requirements.txt because they need unconvinient system dependencies
     PIP="$(wget https://raw.githubusercontent.com/ribaguifi/django-orchestra/dev/github-actions/requirements.txt -O - | tr '\n' ' ') \
-        cracklib \
-        lxml==3.3.5"
+        cracklib"
     if $testing; then
         PIP="${PIP} \
             selenium \