[CI][Diffusion] Add tiny model builder for StableDiffusion3Pipeline (#6423)

Signed-off-by: khairulkabir1661 <khairulkabir1661@users.noreply.github.com>
Co-authored-by: khairulkabir1661 <khairulkabir1661@users.noreply.github.com>

tests/model_tests/diffusion/model_settings.py

@@ -146,4 +146,9 @@ DIFFUSION_TEST_SETTINGS = {
         builder=diff_model_builders.tiny_qwen_image_edit_plus_builder,
         supported_tasks=[DiffusionTasks.IMAGE_TO_IMAGE],
     ),
+    "StableDiffusion3Pipeline": DiffusionModelTestOpts(
+        model="stabilityai/stable-diffusion-3.5-medium",
+        builder=diff_model_builders.tiny_sd3_builder,
+        supported_tasks=[DiffusionTasks.TEXT_TO_IMAGE],
+    ),
 }