chore(env): update MAGE_X_VERSION to v1.8.15

Author: mrz1836

.github/.env.base

@@ -244,7 +244,7 @@ REDIS_CACHE_FORCE_PULL=false           # Force pull Redis images even when cache
 # 🪄 MAGE-X CONFIGURATION
 # ================================================================================================
 
-MAGE_X_VERSION=v1.8.14                                        # https://github.com/mrz1836/mage-x/releases
+MAGE_X_VERSION=v1.8.15                                        # https://github.com/mrz1836/mage-x/releases
 MAGE_X_USE_LOCAL=false                                        # Use local version for development
 MAGE_X_AUTO_DISCOVER_BUILD_TAGS=true                          # Enable auto-discovery of build tags
 MAGE_X_AUTO_DISCOVER_BUILD_TAGS_EXCLUDE=race,custom           # Comma-separated list of tags to exclude