fix: lms progress issue

[pateljannat]

Issue:

1. For LMS, enroll in Program but don't enroll in its courses.
2. Visit the LMS. Click on the Program. It results in an error.

Traceback (most recent call last):
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/website/render.py", line 49, in render
    data = render_page_by_language(path)
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/website/render.py", line 178, in render_page_by_language
    return render_page(path)
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/website/render.py", line 194, in render_page
    return build(path)
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/website/render.py", line 201, in buildreturn build_page(path)
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/website/render.py", line 224, in build_page
    html = frappe.get_template(context.template).render(context)
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/environment.py", line 1090, in render
    self.environment.handle_exception()
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/environment.py", line 832, in handle_exception
    reraise(*rewrite_traceback_stack(source=source))
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/_compat.py", line 28, in reraise
    raise value.with_traceback(tb)
  File "/home/frappe/frappe-io-bench/apps/erpnext/erpnext/./www/lms/program.html", line 62, in top-level template code
    <span class="indicator blue">{{_('Start')}}</span>
  File "/home/frappe/frappe-io-bench/apps/frappe/frappe/./templates/base.html", line 83, in top-level template code
    {% block content %}
  File "/home/frappe/frappe-io-bench/apps/erpnext/erpnext/./www/lms/program.html", line 77, in block "content"
    {{ card(course) }}
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/sandbox.py", line 462, in callreturn __context.call(__obj, *args, **kwargs)
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/runtime.py", line 679, in _invoke
    rv = self._func(*arguments)
  File "/home/frappe/frappe-io-bench/apps/erpnext/erpnext/./www/lms/program.html", line 55, in template
    {% if has_access and progress[course.name] %}
  File "/home/frappe/frappe-io-bench/env/lib/python3.6/site-packages/jinja2/sandbox.py", line 384, in getitem
    return obj[argument]
jinja2.exceptions.UndefinedError: 'progress' is undefined