Move the long name of warning to the next line.

Author: armiol

datastore/src/main/java/io/spine/server/storage/datastore/DsColumnMapping.java

@@ -169,7 +169,8 @@ protected ColumnTypeMapping<Message, StringValue> ofMessage() {
     /**
      * Returns the default mapping from {@link Timestamp} to {@link TimestampValue}.
      */
-    @SuppressWarnings({"ProtoTimestampGetSecondsGetNano" /* In order to create exact value. */,
+    @SuppressWarnings({
+            "ProtoTimestampGetSecondsGetNano" /* In order to create exact value. */,
             "UnnecessaryLambda" /* For brevity.*/,
             "WeakerAccess" /* To allow access for SPI users. */})
     protected static ColumnTypeMapping<Timestamp, TimestampValue> ofTimestamp() {