Resolve "Creating non-timeslot lab requires opening time of slots"

What does this mr do?

This mr makes the slot selection opens at date time picker disabled if no slot selections are selected.

Actions taken to fix bug

Create a javascript toggle that toggles it whether it is selected.

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made and the bug I fixed.
• A test was created to test the bug.
• I have updated the documentation accordingly.
• I adhere to the style guide.

Closes #335 (closed)

src/main/resources/templates/lab/create.html

@@ -315,10 +315,12 @@
 
             $('#slotOpensAt')
                 .on('change.datetimepicker', function (e) {
-                    newDate = e.date.add(225, 'minutes');
+                    const newDate = e.date.add(225, 'minutes');
                     $('#slotClosesAt').datetimepicker('date', newDate);
                 });
 
+            toggleTimeIntervals();
+
             $('#inputTimeIntervals').change(function () {
                 toggleTimeIntervals();
             });
@@ -338,11 +340,11 @@
             if ($('input[name=signOffIntervals]').is(':checked')) {
                 $('#intervalTime').prop('disabled', false);
                 $('#capacity').prop('disabled', false);
-                $('#slotSelectionOpensAt').prop('disabled', false);
+                $('#slotSelectionOpensAt input').prop('disabled', false);
             } else {
                 $('#intervalTime').prop('disabled', true);
                 $('#capacity').prop('disabled', true);
-                $('#slotSelectionOpensAt').prop('disabled', true);
+                $('#slotSelectionOpensAt input').prop('disabled', true);
                 $('#inputExamLab').prop('checked', false);
                 $('#percentageExamLab').prop('disabled', true)
             }