Fix behaviour of DependencyCustomizer ifAllResourcesPresent

Previously, DependencyCustomizer's ifAllResourcesPresent method
would return a customizer that added modules if any of the resources
were present. This commit corrects this behaviours so that modules are
only added if all resources are present.

Fixes gh-20418

spring-boot-project/spring-boot-cli/src/main/java/org/springframework/boot/cli/compiler/DependencyCustomizer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2019 the original author or authors.
+ * Copyright 2012-2020 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.
@@ -144,7 +144,6 @@ public class DependencyCustomizer {
 						if (DependencyCustomizer.this.loader.getResource(path) == null) {
 							return false;
 						}
-						return true;
 					}
 					catch (Exception ex) {
 						// swallow exception and continue