Fix metadata of management.otlp.metrics.export.base-time-unit

See gh-37094

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -2054,6 +2054,10 @@
         "level": "error"
       }
     },
+    {
+      "name": "management.otlp.metrics.export.base-time-unit",
+      "defaultValue": "milliseconds"
+    },
     {
       "name": "management.otlp.tracing.compression",
       "defaultValue": "none"