PY-23164 Fixed: unittest unresolved attribute reference in setUp inside with statement

Don't skip with-statement children while collecting target expressions inside function.

python/src/com/jetbrains/python/psi/impl/PyClassImpl.java

@@ -1222,6 +1222,8 @@ public class PyClassImpl extends PyBaseElementImpl<PyClassStub> implements PyCla
             .map(PyWithItem::getTarget)
             .select(PyTargetExpression.class)
             .forEach(result::add);
+
+          super.visitPyWithStatement(node);
         }
       });
       return result;

python/testData/inspections/PyUnresolvedReferencesInspection/instanceAttributeCreatedInsideWithStatement.py

@@ -0,0 +1,8 @@
+class Foo(object):
+    def __init__(self):
+        with open('b.py'):
+            self.scope = "a"
+            pass
+
+    def get_scope(self):
+        return self.scope

python/testSrc/com/jetbrains/python/inspections/PyUnresolvedReferencesInspectionTest.java

@@ -758,6 +758,11 @@ public class PyUnresolvedReferencesInspectionTest extends PyInspectionTestCase {
     assertNotParsed((PyFile)fooPsiFile);
   }
 
+  // PY-23164
+  public void testInstanceAttributeCreatedInsideWithStatement() {
+    doTest();
+  }
+
   @NotNull
   @Override
   protected Class<? extends PyInspection> getInspectionClass() {