Fix incorrect json output format for ConstantPragma and IncorrectSolc

slither/detectors/attributes/constant_pragma.py

@@ -37,7 +37,8 @@ class ConstantPragma(AbstractDetector):
 
             json = self.generate_json_result(info)
             # follow the same format than add_nodes_to_json
-            json['expressions'] = [{'expression': p.version,
+            json['elements'] = [{'type': 'expression',
+                                 'expression': p.version,
                                  'source_mapping': p.source_mapping} for p in pragma]
             results.append(json)
 

slither/detectors/attributes/incorrect_solc.py

@@ -93,7 +93,8 @@ We recommend avoiding complex pragma statement.'''
             json = self.generate_json_result(info)
 
             # follow the same format than add_nodes_to_json
-            json['expressions'] = [{'expression': p.version,
+            json['elements'] = [{'type': 'expression',
+                                 'expression': p.version,
                                  'source_mapping': p.source_mapping} for (reason, p) in disallowed_pragmas]
             results.append(json)