Add release notes from 0.15.3 and 0.15.4

ride-the-lightning/umbrel-app.yml

@@ -40,18 +40,16 @@ gallery:
   - 2.jpg
   - 3.jpg
 releaseNotes: >-
-  - Integration with mempool.space api to display prevailing fee rates on various channel open/close modals
+  - Added support to send payments for AMP invoices on LND
 
-  - Links enabled for viewing transactions on mempool.space from modals of on-chain transactions and channel info
+  - Improved authentication logic for clearer error handling and validation during login and password reset processes
 
-  - Added a new config param blockExplorerUrl (-e BLOCK_EXPLORER_URL) to customize for a local/testnet instances of mempool.space  
+  - Refined application settings handling to ensure stricter validation of access keys
 
-  - CPFP enabled on pending on-chain receive transactions (including funds expected from coop close)
+  - Bug fixes
 
-  - Simplification of pending channel open fee bumping modal
 
-
-  Full release notes for boltz-client can be found at https://github.com/BoltzExchange/boltz-client/releases
+  Full release notes can be found at https://github.com/Ride-The-Lightning/RTL/releases
 path: ""
 defaultUsername: ""
 deterministicPassword: true