nijie: fix artist url normalization.

app/logical/sources/strategies/base.rb

@@ -116,7 +116,7 @@ module Sources
       # Sources::Strategies.find("http://dic.pixiv.net/a/THUNDERproject").normalizable_for_artist_finder?
       # => false
       def normalizable_for_artist_finder?
-        false
+        normalize_for_artist_finder.present?
       end
 
       def normalize_for_artist_finder

app/logical/sources/strategies/nijie.rb

@@ -1,6 +1,7 @@
 module Sources
   module Strategies
     class Nijie < Base
+      PROFILE = %r!\Ahttps?://nijie.info/members\.php\?id=(?<member_id>\d+)\z!i
       PICTURE = %r{pic\d+\.nijie.info/nijie_picture/}
       PAGE = %r{\Ahttps?://nijie\.info/view\.php.+id=\d+}
       DIFF = %r!\Ahttps?://pic\d+\.nijie\.info/__rs_l120x120/nijie_picture/diff/main/[0-9_]+\.\w+\z!i
@@ -46,6 +47,8 @@ module Sources
       end
 
       def profile_url
+        return url if url =~ PROFILE
+
         links = page.search("a.name")
 
         if links.any?