Revert unicode character workaround from

https://github.com/edx-solutions/xblock-drag-and-drop-v2/pull/48.

While working on getting the Drag and Drop v2 XBlock ready for edx.org,
we discovered a bug in xblock-utils that kept resources containing
non-ASCII chars from being loaded correctly. This bug was fixed in
https://github.com/edx/xblock-utils/pull/36, and the fix was integrated
into edx-platform via
https://github.com/edx/edx-platform/pull/11282 (target branch: named-release/dogwood.rc) and
https://github.com/edx/edx-platform/pull/11283 (target branch: master).

drag_and_drop_v2/templates/html/js_templates.html

@@ -110,7 +110,7 @@
         </div>
         <div class="row advanced">
           <label for="item-{{id}}-numerical-margin">
-            {{i18n "Margin +/- (when a numerical value is required, values entered by students must not differ from the expected value by more than this margin; default is zero)"}}
+            {{i18n "Margin ± (when a numerical value is required, values entered by students must not differ from the expected value by more than this margin; default is zero)"}}
           </label>
           <input type="number"
                  step="0.1"

requirements.txt

-git+https://github.com/edx/xblock-utils.git@v1.0.0#egg=xblock-utils==v1.0.0
+git+https://github.com/edx/xblock-utils.git@v1.0.2#egg=xblock-utils==1.0.2
 -e .