chore: fix depr warning by updating import: xblockutils -> xblock.utils

Context: openedx/XBlock#675

This fixes some edx-platform warnings:

    /openedx/venv/lib/python3.8/site-packages/poll/poll.py:40:
    DeprecatedPackageWarning: Please use import xblock.utils.publish_event instead of
    xblockutils.publish_event because the 'xblock-utils' package has been deprecated and
    migrated to within 'xblock' package.

Uses a try-catch for backwards compatibility with pre-Quince versions
of xblock and xblockutils.

Bump from 1.13.0 to 1.13.1

poll/poll.py

@@ -37,9 +37,15 @@
 from xblock.core import XBlock
 from xblock.fields import Boolean, Dict, Integer, List, Scope, String
 from web_fragments.fragment import Fragment
-from xblockutils.publish_event import PublishEventMixin
-from xblockutils.resources import ResourceLoader
-from xblockutils.settings import ThemableXBlockMixin, XBlockWithSettingsMixin
+
+try:
+    from xblock.utils.publish_event import PublishEventMixin
+    from xblock.utils.resources import ResourceLoader
+    from xblock.utils.settings import ThemableXBlockMixin, XBlockWithSettingsMixin
+except ImportError:  # For backward compatibility with releases older than Quince.
+    from xblockutils.publish_event import PublishEventMixin
+    from xblockutils.resources import ResourceLoader
+    from xblockutils.settings import ThemableXBlockMixin, XBlockWithSettingsMixin
 
 from .utils import DummyTranslationService, _, remove_markdown_and_html_tags
 

setup.py

@@ -48,7 +48,7 @@ def package_data(pkg, roots):
 
 setup(
     name='xblock-poll',
-    version='1.13.0',
+    version='1.13.1',
     description='An XBlock for polling users.',
     long_description=README,
     long_description_content_type='text/markdown',

tests/integration/base_test.py

@@ -22,9 +22,12 @@
 #
 
 from __future__ import absolute_import
-from xblockutils.base_test import SeleniumBaseTest
 from mock import patch
 
+try:
+    from xblock.utils.base_test import SeleniumBaseTest
+except ImportError:  # For backward compatibility with releases older than Quince.
+    from xblockutils.base_test import SeleniumBaseTest
 
 # Default names for inputs for polls/surveys
 DEFAULT_SURVEY_NAMES = ('enjoy', 'recommend', 'learn')