Create git commit time with epoch seconds rather than milliseconds

Closes gh-33237

Author: wilkinsona

spring-boot-project/spring-boot-actuator-autoconfigure/src/test/java/org/springframework/boot/actuate/autoconfigure/endpoint/web/documentation/InfoEndpointDocumentationTests.java

@@ -16,6 +16,7 @@
 
 package org.springframework.boot.actuate.autoconfigure.endpoint.web.documentation;
 
+import java.time.Instant;
 import java.util.List;
 import java.util.Properties;
 
@@ -83,7 +84,7 @@ GitInfoContributor gitInfoContributor() {
 			properties.put("branch", "main");
 			properties.put("commit.id", "df027cf1ec5aeba2d4fedd7b8c42b88dc5ce38e5");
 			properties.put("commit.id.abbrev", "df027cf");
-			properties.put("commit.time", Long.toString(System.currentTimeMillis()));
+			properties.put("commit.time", Long.toString(Instant.now().getEpochSecond()));
 			GitProperties gitProperties = new GitProperties(properties);
 			return new GitInfoContributor(gitProperties);
 		}