🆕 #2998 【小程序】增加获取稳定版接口调用凭据的接口，通过设置WxMaConfig#useStableAccessToken方法去开启使用稳定版接口

weixin-java-miniapp/src/main/java/cn/binarywang/wx/miniapp/bean/WxMaStableAccessTokenRequest.java

@@ -0,0 +1,34 @@
+package cn.binarywang.wx.miniapp.bean;
+
+import cn.binarywang.wx.miniapp.json.WxMaGsonBuilder;
+import com.google.gson.annotations.SerializedName;
+import lombok.Data;
+
+import java.io.Serializable;
+
+/**
+ * 小程序码.
+ *
+ * @author Element
+ * created on  2017/7/27
+ */
+@Data
+public class WxMaStableAccessTokenRequest implements Serializable {
+
+  private static final long serialVersionUID = 1L;
+
+  @SerializedName("grant_type")
+  private String grantType = "client_credential";
+
+  @SerializedName("appid")
+  private String appid;
+  @SerializedName("secret")
+  private String secret;
+
+  @SerializedName("force_refresh")
+  private boolean forceRefresh;
+
+  public String toJson() {
+    return WxMaGsonBuilder.create().toJson(this);
+  }
+}