Polish "Deprecate Spring Data Solr"

See gh-24942

Author: snicoll

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

@@ -686,7 +686,11 @@
       "name": "spring.data.solr.repositories.enabled",
       "type": "java.lang.Boolean",
       "description": "Whether to enable Solr repositories.",
-      "defaultValue": true
+      "defaultValue": true,
+      "deprecation": {
+        "reason": "Spring Data Solr is deprecated.",
+        "level": "warning"
+      }
     },
     {
       "name": "spring.datasource.initialization-mode",