Fix deprecated ISO8601DateFormat usage

Author: slonopotamus

gitlfs-common/src/main/java/ru/bozaro/gitlfs/common/JsonHelper.java

@@ -6,7 +6,7 @@
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.SerializationFeature;
-import com.fasterxml.jackson.databind.util.ISO8601DateFormat;
+import com.fasterxml.jackson.databind.util.StdDateFormat;
 import org.jetbrains.annotations.NotNull;
 
 import java.text.DateFormat;
@@ -17,17 +17,17 @@
  * Json utility class.
  *
  * @author Artem V. Navrotskiy
- * @author Marat Radchenko <marat@slonopootamus.org>
+ * @author Marat Radchenko <marat@slonopotamus.org>
  */
 public final class JsonHelper {
 
   /**
-   * git-lfs is broken and doesn't properly parse output of {@link com.fasterxml.jackson.databind.util.StdDateFormat}.
+   * git-lfs cannot parse timezone without colon: {@link com.fasterxml.jackson.databind.util.StdDateFormat}.
    * <p/>
    * See https://github.com/git-lfs/git-lfs/issues/3660
    */
   @NotNull
-  public static final DateFormat dateFormat = new ISO8601DateFormat();
+  public static final DateFormat dateFormat = StdDateFormat.instance.withColonInTimeZone(true);
 
   @NotNull
   public static final ObjectMapper mapper = new ObjectMapper();

gitlfs-common/src/test/java/ru/bozaro/gitlfs/common/data/DateTest.java

@@ -10,7 +10,7 @@ public final class DateTest {
 
   @Test
   public void format() throws ParseException {
-    final String str = "2006-01-02T15:04:05Z";
+    final String str = "2006-01-02T15:04:05.123+00:00";
     Assert.assertEquals(JsonHelper.dateFormat.format(JsonHelper.dateFormat.parse(str)), str);
   }
 }