Change Liberapay entry to username only

Updated Liberapay username to remove URL.

.github/FUNDING.yml

@@ -6,7 +6,7 @@ open_collective: # Replace with a single Open Collective username
 ko_fi: # Replace with a single Ko-fi username
 tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
 community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
-liberapay: https://liberapay.com/Seb3thehacker
+liberapay: Seb3thehacker
 issuehunt: # Replace with a single IssueHunt username
 lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
 polar: # Replace with a single Polar username