Use SECRET_KEY_BASE_DUMMY feature as placeholder during asset compilation (#30505)

.github/workflows/test-ruby.yml

@@ -28,11 +28,7 @@ jobs:
     env:
       RAILS_ENV: ${{ matrix.mode }}
       BUNDLE_WITH: ${{ matrix.mode }}
-      ACTIVE_RECORD_ENCRYPTION_DETERMINISTIC_KEY: precompile_placeholder
-      ACTIVE_RECORD_ENCRYPTION_KEY_DERIVATION_SALT: precompile_placeholder
-      ACTIVE_RECORD_ENCRYPTION_PRIMARY_KEY: precompile_placeholder
-      OTP_SECRET: precompile_placeholder
-      SECRET_KEY_BASE: precompile_placeholder
+      SECRET_KEY_BASE_DUMMY: 1
 
     steps:
       - uses: actions/checkout@v4