Polish "Improve error message when no resources exist at a script location"

See gh-25620

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/jdbc/DataSourceInitializer.java

@@ -161,7 +161,7 @@ class DataSourceInitializer {
 				}
 				else if (validate) {
 					throw new InvalidConfigurationPropertyValueException(propertyName, resource,
-							"Resource '" + location + "' does not exist.");
+							"No resources were found at location '" + location + "'.");
 				}
 			}
 		}

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/jdbc/DataSourceInitializerInvokerTests.java

@@ -223,8 +223,8 @@ class DataSourceInitializerInvokerTests {
 					assertThat(context.getStartupFailure()).isInstanceOf(BeanCreationException.class);
 					assertThat(context.getStartupFailure()).hasMessageContaining("[does/not/exist.sql]");
 					assertThat(context.getStartupFailure()).hasMessageContaining("spring.datasource.schema");
-					assertThat(context.getStartupFailure())
+					assertThat(context.getStartupFailure()).hasMessageContaining(
-							.hasMessageContaining("Resource 'classpath:does/not/exist.sql' does not exist.");
+							"No resources were found at location 'classpath:does/not/exist.sql'.");
 				});
 	}
 
@@ -237,8 +237,8 @@ class DataSourceInitializerInvokerTests {
 					assertThat(context.getStartupFailure()).isInstanceOf(BeanCreationException.class);
 					assertThat(context.getStartupFailure()).hasMessageContaining("[does/not/exist.sql]");
 					assertThat(context.getStartupFailure()).hasMessageContaining("spring.datasource.data");
-					assertThat(context.getStartupFailure())
+					assertThat(context.getStartupFailure()).hasMessageContaining(
-							.hasMessageContaining("Resource 'classpath:does/not/exist.sql' does not exist.");
+							"No resources were found at location 'classpath:does/not/exist.sql'.");
 				});
 	}