Minor fixes

* Address review comment by replacing variable name image to tag.
* Remove regex compilation flag to avoid confusion. Previous regex match
  did not use it.
* Remove unused import.

Signed-off-by: Chenxiong Qi <[email protected]>

config/registry_image_pruner/image_pruner/prune_images.py

@@ -7,7 +7,7 @@
 
 from collections.abc import Iterator
 from http.client import HTTPResponse
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List
 from urllib.parse import urlencode
 from urllib.request import Request, urlopen
 
@@ -48,18 +48,18 @@ def delete_image_repo(quay_token: str, namespace: str, name: str, tag: str) -> N
 
 def remove_images(images: Dict[str, Any], quay_token: str, namespace: str, name: str, dry_run: bool = False) -> None:
     image_digests = [image["manifest_digest"] for image in images.values()]
-    image_regex = re.compile(r"^sha256-([0-9a-f]+)(\.sbom|\.att)$", re.IGNORECASE)
-    for image in images:
+    image_regex = re.compile(r"^sha256-([0-9a-f]+)(\.sbom|\.att)$")
+    for tag in images:
         # attestation or sbom image
-        if (match := image_regex.match(image)) is not None:
+        if (match := image_regex.match(tag)) is not None:
             if f"sha256:{match.group(1)}" not in image_digests:
                 if dry_run:
-                    LOGGER.info("Image %s from %s/%s should be removed", image, namespace, name)
+                    LOGGER.info("Image %s from %s/%s should be removed", tag, namespace, name)
                 else:
-                    LOGGER.info("Removing image %s from %s/%s", image, namespace, name)
-                    delete_image_repo(quay_token, namespace, name, image)
+                    LOGGER.info("Removing image %s from %s/%s", tag, namespace, name)
+                    delete_image_repo(quay_token, namespace, name, tag)
         else:
-            LOGGER.debug("%s is not an image with suffix .att or .sbom", image)
+            LOGGER.debug("%s is not an image with suffix .att or .sbom", tag)
 
 
 def process_repositories(repos: List[ImageRepo], quay_token: str, dry_run: bool = False) -> None: