Replace deprecated SNAKE_CASE with current SNAKE_CASE (#1807)

Jackson API 2.20.0 removes the PropertyNamingStrategy.SNAKE_CASE symbol.
The replacement symbol is PropertyNamingStrategies.SNAKE_CASE.

Refer to BOM test failures in:

* jenkinsci/bom#5622

Testing done:

Confirmed it compiles with Jackson 2 API 2.20.0 incremental build and
with current Jackson 2 API 2.19.x.

Co-authored-by: Basil Crow <[email protected]>
Co-authored-by: Kris Stern <[email protected]>

Author: 3 people

src/main/java/com/dabsquared/gitlabjenkins/gitlab/JacksonConfig.java

@@ -2,7 +2,7 @@
 
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.PropertyNamingStrategy;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import javax.ws.rs.Consumes;
 import javax.ws.rs.Produces;
 import javax.ws.rs.core.MediaType;
@@ -18,7 +18,7 @@
 public class JacksonConfig implements ContextResolver<ObjectMapper> {
     public ObjectMapper getContext(Class<?> type) {
         return new ObjectMapper()
-                .setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE)
+                .setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE)
                 .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
                 .configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL, true);
     }

src/main/java/com/dabsquared/gitlabjenkins/util/JsonUtil.java

@@ -4,7 +4,7 @@
 import com.fasterxml.jackson.databind.DeserializationFeature;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
-import com.fasterxml.jackson.databind.PropertyNamingStrategy;
+import com.fasterxml.jackson.databind.PropertyNamingStrategies;
 import com.fasterxml.jackson.databind.SerializationFeature;
 import com.fasterxml.jackson.databind.module.SimpleModule;
 import java.io.IOException;
@@ -20,7 +20,7 @@
 public final class JsonUtil {
 
     private static final ObjectMapper OBJECT_MAPPER = new ObjectMapper()
-            .setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE)
+            .setPropertyNamingStrategy(PropertyNamingStrategies.SNAKE_CASE)
             .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
             .configure(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL, true)
             .configure(SerializationFeature.INDENT_OUTPUT, true)