Fix typo in ApplicationContextAssert

See gh-18372

Author: rweisleder

spring-boot-project/spring-boot-test/src/main/java/org/springframework/boot/test/context/assertj/ApplicationContextAssert.java

@@ -175,7 +175,7 @@ public ApplicationContextAssert<C> doesNotHaveBean(Class<?> type, Scope scope) {
 		String[] names = scope.getBeanNamesForType(getApplicationContext(), type);
 		if (names.length > 0) {
 			throwAssertionError(new BasicErrorMessageFactory(
-					"%nExpecting:%n <%s>%nnot to have a beans of type:%n <%s>%nbut found:%n <%s>",
+					"%nExpecting:%n <%s>%nnot to have any beans of type:%n <%s>%nbut found:%n <%s>",
 					getApplicationContext(), type, names));
 		}
 		return this;