[kemonoparty] Support /posts endpoint and Creator Tag Calls

- Adding support for calling a creator with a tag selected.
    It is using a legacy endpoint but there is no other way currently
    documented to get the users post filtered by a tag.
- Fixing the User Tags feature to be paginated
    offset is not defined in the API but it is supported.
- Fixed the `/posts` endpoint not working:
    1. Added check along with metadata to make sure there is a
       creator/service information as that is a requirement
    2. Fixed the parameter from tags -> tag.
    3. Fixed the _paginate call to exit correctly when there is
       a key required for the data (it was prematurely exiting)
- Adding a type of caching mechanism for the metadata/user information.
    The current logic would work just fine if looking up for a
    singular user, however for the multiple posts via normal
    filtering would cause it to either:
    This builds a local cache during the process so it should
    only make a call for the user info once during the process.
- Updating to meet standards
    Fixes
      1. Reset formatting for unnecessary line changes
      2. Removed Type Hinting
      3.Replaced f-string with "".format
   Updates
     Renamed function creator_posts_tags -> creator_tagged_posts
     for clarity of what it does (get posts tags vs get tagged posts)
- Fixing check for the length of response:
    1. If it is list - just check len
    2. If there is a key - check that the key length is less
       than the batch.
- add test for '?tag=...' user URLs
    plus some code simplifications

test/results/kemonoparty.py

@@ -39,6 +39,21 @@ __tests__ = (
     "id": "8779",
 },
 
+{
+    "#url"     : "https://kemono.su/patreon/user/3161935?tag=pin-up",
+    "#comment" : "'tag' query parameter",
+    "#category": ("", "kemonoparty", "patreon"),
+    "#class"   : kemonoparty.KemonopartyUserExtractor,
+    "#urls"    : (
+        "https://kemono.su/data/03/e6/03e62592c3b616b8906c1aaa130bd9ceaa24d7f601b31f90cc11956a57ca1d82.png",
+        "https://kemono.su/data/6a/9b/6a9b6d93dcb86c24a48def1bb93ce2a9ad77393941f3469d87d39400433cf825.png",
+        "https://kemono.su/data/2a/b8/2ab8ba30644249e9516afaea05d61c0de14591cb9d232a2dc249650eb1a9a759.jpg",
+        "https://kemono.su/data/b0/38/b03882c8b0ab3b1cf9fc658a2bb2f9ac6ad4f3449015311dcd2d7ee7f748db31.png",
+    ),
+
+    "tags": r"\bpin-up\b",
+},
+
 {
     "#url"     : "https://kemono.su/subscribestar/user/alcorart",
     "#category": ("", "kemonoparty", "subscribestar"),
@@ -379,7 +394,7 @@ __tests__ = (
     "#category": ("", "kemonoparty", "discord-server"),
     "#class"   : kemonoparty.KemonopartyDiscordServerExtractor,
     "#pattern" : kemonoparty.KemonopartyDiscordExtractor.pattern,
-    "#count"   : 15,
+    "#count"   : 26,
 },
 
 {