Update the import statement for xblock-utils

The `xblock-utils` library has been deprecated as a separate package;
the `utils` library has been moved into the `XBlock` and should now
be imported from `xblock.utils` instead.
(openedx/XBlock#675)

markdown_xblock/html.py

@@ -9,9 +9,9 @@
 from xblock.core import XBlock
 from xblock.fields import List, Scope, String
 from xblock.fragment import Fragment
-from xblockutils.resources import ResourceLoader
-from xblockutils.settings import XBlockWithSettingsMixin
-from xblockutils.studio_editable import StudioEditableXBlockMixin, loader
+from xblock.utils.resources import ResourceLoader
+from xblock.utils.settings import XBlockWithSettingsMixin
+from xblock.utils.studio_editable import StudioEditableXBlockMixin, loader
 
 from .utils import _
 

requirements/base.txt

@@ -1,6 +1,5 @@
 # Requirements for app run
 
-xblock-utils<=4.0.0
 xblock-sdk<0.9.0
 django-statici18n<2.5
 edx-i18n-tools<1.4