python scripts: Use "not in" operator to test membership

As per suggestion from Pyls, this changes
  if not needle in haystack:
to
  if needle not in haystack:

Change-Id: I4a482604e13e61ecee9e02935479632419710ff7
Reviewed-by: hjk <hjk@qt.io>
Reviewed-by: Robert Loehning <robert.loehning@qt.io>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

share/qtcreator/debugger/dumper.py

@@ -1078,7 +1078,7 @@ class DumperBase:
 
         reslist = []
         for item in res.get('variables', {}):
-            if not 'iname' in item:
+            if 'iname' not in item:
                 item['iname'] = '.' + item.get('name')
             reslist.append(self.variablesToMi(item, 'local'))
 

share/qtcreator/debugger/lldbbridge.py

@@ -2216,7 +2216,7 @@ class SyntheticChildrenProvider(SummaryProvider):
         SummaryProvider.update(self)
 
         self.synthetic_children = []
-        if not 'children' in self.summary:
+        if 'children' not in self.summary:
             return
 
         dereference_child = None