Display same symbol for "not equal" operator in "Select by attribute"…

… algorithm

as in "Extract by attribute" algorithm and "select features by value" function

(cherry-picked from 8a1964f)

python/plugins/processing/algs/qgis/SelectByAttribute.py

@@ -48,7 +48,7 @@ class SelectByAttribute(QgisAlgorithm):
     OUTPUT = 'OUTPUT'
 
     OPERATORS = ['=',
-                 '!=',
+                 '≠',
                  '>',
                  '>=',
                  '<',
@@ -80,7 +80,7 @@ def flags(self):
 
     def initAlgorithm(self, config=None):
         self.operators = ['=',
-                          '!=',
+                          '≠',
                           '>',
                           '>=',
                           '<',