Give kibana user privileges to create APM agent config index (#46765) (#46793)

* Give kibana user reserved role privileges on .apm-* to create APM agent configuration index.

* fixed test to include checking all .apm-* permissions

* changed pattern from ".apm-*" to the more specific ".apm-agent-configuration"

Author: ogupte

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/security/authz/store/ReservedRolesStore.java

@@ -123,6 +123,9 @@ private static Map<String, RoleDescriptor> initializeReservedRoles() {
                                 // .code_internal-* is for Code's internal worker queue index creation.
                                 RoleDescriptor.IndicesPrivileges.builder()
                                         .indices(".code-*", ".code_internal-*").privileges("all").build(),
+                                // .apm-* is for APM's agent configuration index creation
+                                RoleDescriptor.IndicesPrivileges.builder()
+                                        .indices(".apm-agent-configuration").privileges("all").build(),
                         },
                         null,
                         new ConfigurableClusterPrivilege[] { new ManageApplicationPrivileges(Collections.singleton("kibana-*")) },

x-pack/plugin/core/src/test/java/org/elasticsearch/xpack/core/security/authz/store/ReservedRolesStoreTests.java

@@ -334,7 +334,12 @@ public void testKibanaSystemRole() {
         assertThat(kibanaRole.indices().allowedIndicesMatcher(IndexAction.NAME).test(".reporting"), is(false));
         assertThat(kibanaRole.indices().allowedIndicesMatcher("indices:foo").test(randomAlphaOfLengthBetween(8, 24)), is(false));
 
-        Arrays.asList(".kibana", ".kibana-devnull", ".reporting-" + randomAlphaOfLength(randomIntBetween(0, 13))).forEach((index) -> {
+        Arrays.asList(
+            ".kibana",
+            ".kibana-devnull",
+            ".reporting-" + randomAlphaOfLength(randomIntBetween(0, 13)),
+            ".apm-agent-configuration"
+        ).forEach((index) -> {
             logger.info("index name [{}]", index);
             assertThat(kibanaRole.indices().allowedIndicesMatcher("indices:foo").test(index), is(true));
             assertThat(kibanaRole.indices().allowedIndicesMatcher("indices:bar").test(index), is(true));