Merge pull request #1414 from SimonCropp/remove-some-duplicate-dictionary-lookups2

remove some duplicate dictionary lookups

Author: baywet

src/Microsoft.OpenApi.Readers/V2/OpenApiResponseDeserializer.cs

@@ -122,9 +122,9 @@ private static void LoadExample(OpenApiResponse response, string mediaType, Pars
             }
 
             OpenApiMediaType mediaTypeObject;
-            if (response.Content.ContainsKey(mediaType))
+            if (response.Content.TryGetValue(mediaType, out var value))
             {
-                mediaTypeObject = response.Content[mediaType];
+                mediaTypeObject = value;
             }
             else
             {

src/Microsoft.OpenApi/Validations/Rules/RuleHelpers.cs

@@ -87,9 +87,10 @@ public static void ValidateDataTypeMismatch(
                 {
                     context.Enter(key);
 
-                    if (schema.Properties != null && schema.Properties.ContainsKey(key))
+                    if (schema.Properties != null &&
+                        schema.Properties.TryGetValue(key, out var property))
                     {
-                        ValidateDataTypeMismatch(context, ruleName, anyObject[key], schema.Properties[key]);
+                        ValidateDataTypeMismatch(context, ruleName, anyObject[key], property);
                     }
                     else
                     {