Upgrade to Nullability Plugin 0.0.9

Closes gh-48638

cli/spring-boot-cli/build.gradle

@@ -61,11 +61,8 @@ dependencies {
 	testImplementation(project(":test-support:spring-boot-test-support"))
 }
 
-architectureCheck {
-	nullMarked {
-		enabled  = true
-		ignoredPackages = ['org.springframework.boot.cli.json']
-	}
+nullability {
+	requireExplicitNullMarking = false
 }
 
 tasks.register("fullJar", Jar) {

cli/spring-boot-cli/src/json-shade/java/org/springframework/boot/cli/json/package-info.java

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2012-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+@NullUnmarked
+package org.springframework.boot.cli.json;
+
+import org.jspecify.annotations.NullUnmarked;