Implement the equals and hashCode contracts for Field.

Original Pull Request spring-projects#2859
Closes spring-projects#2858

Author: youssef3wi

src/main/java/org/springframework/data/elasticsearch/core/query/SimpleField.java

@@ -19,6 +19,8 @@
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 
+import java.util.Objects;
+
 /**
  * The most trivial implementation of a Field. The {@link #name} is updatable, so it may be changed during query
  * preparation by the {@link org.springframework.data.elasticsearch.core.convert.MappingElasticsearchConverter}.
@@ -79,4 +81,16 @@ public String getPath() {
 	public String toString() {
 		return getName();
 	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) return true;
+		if (!(o instanceof SimpleField that)) return false;
+        return Objects.equals(name, that.name) && Objects.equals(fieldType, that.fieldType) && Objects.equals(path, that.path);
+	}
+
+	@Override
+	public int hashCode() {
+		return Objects.hash(name, fieldType, path);
+	}
 }