Support Integer to Duration conversion during property binding

Closes gh-11216

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/bind/convert/DurationConverter.java

@@ -45,6 +45,7 @@ class DurationConverter implements GenericConverter {
 	static {
 		Set<ConvertiblePair> types = new LinkedHashSet<>();
 		types.add(new ConvertiblePair(String.class, Duration.class));
+		types.add(new ConvertiblePair(Integer.class, Duration.class));
 		TYPES = Collections.unmodifiableSet(types);
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/properties/bind/convert/BinderConversionServiceTests.java

@@ -161,6 +161,13 @@ public class BinderConversionServiceTests {
 		assertThat(converted).isEqualTo(Duration.ofSeconds(10));
 	}
 
+	@Test
+	public void conversionServiceShouldSupportIntegerToDuration() throws Exception {
+		this.service = new BinderConversionService(null);
+		Duration converted = this.service.convert(10, Duration.class);
+		assertThat(converted).isEqualTo(Duration.ofMillis(10));
+	}
+
 	enum TestEnum {
 
 		ONE, TWO