Only check DHT marker for libjpeg-turbo (#9025)

Author: hugovk

Tests/test_file_jpeg.py

@@ -1067,10 +1067,16 @@ def test_separate_tables(self) -> None:
         for marker in b"\xff\xd8", b"\xff\xd9":
             assert marker in data[1]
             assert marker in data[2]
-        # DHT, DQT
-        for marker in b"\xff\xc4", b"\xff\xdb":
+
+        # DQT
+        markers = [b"\xff\xdb"]
+        if features.check_feature("libjpeg_turbo"):
+            # DHT
+            markers.append(b"\xff\xc4")
+        for marker in markers:
             assert marker in data[1]
             assert marker not in data[2]
+
         # SOF0, SOS, APP0 (JFIF header)
         for marker in b"\xff\xc0", b"\xff\xda", b"\xff\xe0":
             assert marker not in data[1]