update patch notes for v15.8.0

Author: Arne-Weber

patch_notes.txt

@@ -1,8 +1,13 @@
-## v15.7.1
+## v15.8.0
+
+22.7.2024
+- Changed GQL persistant query `DropCampaignDetails` hash to match a change on Twitch's side and prevent `PersistedQueryNotFound` crash on startup.
 
 16.7.2024
 - Updated **French** and **Indonesian** translation
 
+## v15.7.1
+
 1.7.2024
 - Patched bug due to Twitch falsely reporting time claimed
     - Campaigns, that are both repeating **AND** are falsely reported, could still cause issues. Tracked in #139.