Exclude build directories from nohttp task

Before this commit, build directories were considered when running the
checkstyleNohttp Gradle task.

Given that many tasks write their outputs to the build directory, this
could lead to incorrect results being produced, depending on what order
the tasks are executed. As a result, Gradle will disable some build
optimizations, such as build caching, to ensure correctness.

After this commit, build directories are ignored by the
checkstyleNohttp task.

buildSrc/src/main/java/org/springframework/gradle/nohttp/SpringNoHttpPlugin.java

@@ -36,6 +36,6 @@ public void apply(Project project) {
 		NoHttpExtension nohttp = project.getExtensions().getByType(NoHttpExtension.class);
 		File allowlistFile = project.getRootProject().file("etc/nohttp/allowlist.lines");
 		nohttp.setAllowlistFile(allowlistFile);
-		nohttp.getSource().exclude("buildSrc/build/**");
+		nohttp.getSource().exclude("**/build/**");
 	}
 }