[Server 3.0] added missing QgsApplication

Author: elpaso

tests/src/python/test_qgsserver_accesscontrol.py

@@ -24,7 +24,7 @@
 from osgeo import gdal
 from osgeo.gdalconst import GA_ReadOnly
 from qgis.server import QgsServer, QgsAccessControlFilter
-from qgis.core import QgsRenderChecker
+from qgis.core import QgsRenderChecker, QgsApplication
 from qgis.PyQt.QtCore import QSize
 import tempfile
 import urllib.request