Fix for renovate config needs migrating

Description

might fix the warning when running renovate and probably wrong basebranch

config.js

@@ -9,7 +9,7 @@ module.exports = {
   endpoint: process.env.CI_API_V4_URL,
   hostRules: [
     {
-      baseUrl: 'https://registry.code.fbi.h-da.de',
+      matchHost: 'https://registry.code.fbi.h-da.de',
       username: '@project_10161_bot',
       password: process.env.GITLAB_REGISTRY_TOKEN,
     },
@@ -21,5 +21,5 @@ module.exports = {
   prConcurrentLimit: 10,
   commitMessagePrefix: '[renovate]',
   labels: ['renovate'],
-  baseBranches: ['develop']
+  baseBranches: ['mainline']
 };