lowercase email compare

When multiple users are found, do email check case-insensitive.
Also when not found, log the found email address as a set.

Author: abij

src/wordpress_markdown_blog_loader/api.py

@@ -338,10 +338,10 @@ def get_unique_user_by_name(self, name: str, email: Optional[str]) -> "User":
         if len(users) == 0:
             raise ValueError(f"author '{name}' not found on {self.endpoint.host}")
         elif len(users) > 1:
-            user = next(filter(lambda u: email and u.email == email, users), None)
+            user = next(filter(lambda u: email and u.email.lower() == email.lower(), users), None)
             if not user:
                 raise ValueError(
-                    f"Multiple authors named '{name}' found, none with email {email}"
+                    f"Multiple authors named '{name}' found, none with email {email} (possible: { {u.email for u in users} })."
                 )
         return users[0]
 
@@ -546,4 +546,4 @@ def get_tag_id_by_name(self, tag: str) -> str:
             "invalid tag '{}' try one of\n {}".format(
                 tag, ",\n ".join(self.tags.keys())
             )
-        )
+        )