update sponsor in github

Author: erdogant

.github/FUNDING.yml

@@ -1,13 +1,14 @@
 # These are supported funding model platforms
 
 github: [erdogant]
+buy_me_a_coffee: erdogant
+ko_fi: erdogant
+custom: [https://erdogant.github.io/clusteval/pages/html/Documentation.html]
 patreon: # Replace with a single Patreon username
 open_collective: # Replace with a single Open Collective username
-ko_fi: # Replace with a single Ko-fi username
 tidelift: #
 community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
 liberapay: # Replace with a single Liberapay username
 issuehunt: # Replace with a single IssueHunt username
 otechie: # Replace with a single Otechie username
 lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
-custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']