ci: temporarily run main against itself

We don't want the job to fail, and we want to run it to see trends.
Therefore for a while, we will run it against itself.

Author: triceo

.github/workflows/performance_score_director.yml

@@ -27,7 +27,7 @@ on:
         required: true
       baseline:
         description: 'Baseline branch or tag (branches need to use 999-SNAPSHOT)'
-        default: 'v2.0.0-beta-1'
+        default: 'main'
         required: true
       jdk_branch:
         description: 'JDK version'