test: update the test case, that test transformer already supports preserveImageMetadata

Author: dreampiggy

Tests/Tests/SDWebImageTestTransformer.h

@@ -9,9 +9,7 @@
 
 #import <SDWebImage/SDImageTransformer.h>
 
-@interface SDWebImageTestTransformer : NSObject <SDImageTransformer>
-
-@property (nonatomic, assign) BOOL preserveImageMetadata;
+@interface SDWebImageTestTransformer : SDImageBaseTransformer
 
 @property (nonatomic, strong, nullable) UIImage *testImage;
 

Tests/Tests/SDWebImageTestTransformer.m

@@ -11,14 +11,6 @@
 
 @implementation SDWebImageTestTransformer
 
-- (instancetype)init {
-    self = [super init];
-    if (self) {
-        _preserveImageMetadata = YES;
-    }
-    return self;
-}
-
 - (NSString *)transformerKey {
     return @"SDWebImageTestTransformer";
 }