Supply missing extension metadata for reactive keycloak client

(cherry picked from commit 6110d38)

Author: holly-cummins

extensions/keycloak-admin-client-reactive/runtime/src/main/java/resources/META-INF/quarkus-extension.yaml

@@ -0,0 +1,14 @@
+---
+artifact: ${project.groupId}:${project.artifactId}:${project.version}
+name: "Reactive Keycloak Admin Client"
+metadata:
+  keywords:
+  - "keycloak"
+  - "keycloak-admin-client"
+  - "admin"
+  - "openid-connect"
+  - "reactive"
+  categories:
+    - "security"
+    - "reactive"
+  status: "stable"