fix: refactor doc string and test

Signed-off-by: Alex Wu <c.alexwu@gmail.com>

Author: popojk

flytekit/image_spec/noop_builder.py

@@ -8,9 +8,9 @@ class NoOpBuilder(ImageSpecBuilder):
 
     def should_build(self, image_spec: ImageSpec) -> bool:
         """
-        The build_image function of NoOpBuilder uses the image_spec name as defined by the user without
-        checking whether the image exists in the Docker registry. Therefore, the should_build function
-        should always return True to trigger the build_image function.
+        The build_image function of NoOpBuilder does not actually build a Docker image.
+        Since no Docker build process occurs, we do not need to check for Docker daemon
+        or existing images. Therefore, should_build should always return True.
 
         Args:
             image_spec (ImageSpec): Image specification

tests/flytekit/unit/core/image_spec/test_image_spec.py

@@ -364,6 +364,7 @@ def test_noop_builder_updates_image_name_mapping():
     from flytekit.image_spec.noop_builder import NoOpBuilder
 
     # Clear any existing mappings to ensure clean test state
+    ImageBuildEngine._REGISTRY.pop("noop", None)
     ImageBuildEngine._IMAGE_NAME_TO_REAL_NAME.clear()
 
     # Register NoOpBuilder
@@ -391,5 +392,5 @@ def test_noop_builder_updates_image_name_mapping():
     assert actual_real_name == expected_image_name
 
     # Clean up
-    del ImageBuildEngine._REGISTRY["noop"]
+    ImageBuildEngine._REGISTRY.pop("noop", None)
     ImageBuildEngine._IMAGE_NAME_TO_REAL_NAME.clear()