Remove DEBUG_STATIC logic and unused JS libraries

[Gpetrak]

The DEBUG_STATIC setting is currently used in templates (e.g. base.html) to conditionally include individual JavaScript libraries during development:

{% if DEBUG_STATIC %}
    <script src="{% static "lib/js/jquery.js" %}"></script>
    <script src="{% static "lib/js/jquery.dataTables.js" %}"></script>
    <script src="{% static "lib/js/bootstrap-treeview.js" %}"></script>
    <script src="{% static "lib/js/bootstrap-tokenfield.js" %}"></script>
    <script src="{% static "lib/js/fastselect.standalone.js" %}"></script>
    <script src="{% static "lib/js/select2.full.js" %}"></script>
    <script src="{% static "lib/js/jquery.timeago.js" %}"></script>
    <script src="{% static "lib/js/jq-ajax-progress.js" %}"></script>
    <script src="{% static "lib/js/jquery-ui.js" %}"></script>
    <script src="{% static "lib/js/jquery.raty.js" %}"></script>
    <script src="{% static "lib/js/bootstrap.js" %}"></script>
    <script src="{% static "lib/js/moment-with-locales.js" %}"></script>
    <script src="{% static "lib/js/bootstrap-datetimepicker.js" %}"></script>
    <script src="{% static "lib/js/json2.js" %}"></script>
    <script src="{% static "lib/js/waypoints.js" %}"></script>
    <script src="{% static "lib/js/underscore.js" %}"></script>
    {% else %}
    <script src="{% static "lib/js/assets.min.js" %}"></script>
    {% endif %}

However, this setup appears to be outdated and possibly unused:

• The DEBUG_STATIC setting is no longer clearly documented or used actively.
• Many of the conditionally included libraries seem to be legacy JS

Proposed steps:

1. Remove the DEBUG_STATIC setting and all related conditional logic from templates.
2. Investigate the listed JS libraries to determine whether they are still used anywhere on GeoNode.
3. Remove unused or redundant legacy JS libraries from the code

[t-book]

True this comes from a time when genode used jinja2 templates …

[Gpetrak]

@giohappy @mattiagiupponi the PR for this issue is available here: #13189

Note: This issue probably will be moved under an EPIC related with the cleanup of more static-related outdated code. Because of the following:

• In this PR the needed libraries remained after removing of the DEBUG_STATIC setting, are inserted individually (without a bundle)
• So in the next steps, we will remove the Grunt-related files / and unused libraries (the files)
• and we will re-bundle (with a more modern bundler) the remaining static libraries