bump version to 0.2.15 (#313)

Signed-off-by: EmmetZC <EmmetZC@gmail.com>

README.md

@@ -1,5 +1,5 @@
 [![JavaDoc](http://img.shields.io/badge/javadoc-reference-blue.svg)](https://www.javadoc.io/doc/com.github.wechatpay-apiv3/wechatpay-java/latest/index.html)
-![Maven Central](https://img.shields.io/maven-central/v/com.github.wechatpay-apiv3/wechatpay-java?versionPrefix=0.2.14)
+![Maven Central](https://img.shields.io/maven-central/v/com.github.wechatpay-apiv3/wechatpay-java?versionPrefix=0.2.15)
 [![Security Rating](https://sonarcloud.io/api/project_badges/measure?project=wechatpay-apiv3_wechatpay-java&metric=security_rating)](https://sonarcloud.io/summary/overall?id=wechatpay-apiv3_wechatpay-java)
 [![Maintainability Rating](https://sonarcloud.io/api/project_badges/measure?project=wechatpay-apiv3_wechatpay-java&metric=sqale_rating)](https://sonarcloud.io/summary/overall?id=wechatpay-apiv3_wechatpay-java)
 [![Coverage](https://sonarcloud.io/api/project_badges/measure?project=wechatpay-apiv3_wechatpay-java&metric=coverage)](https://sonarcloud.io/summary/overall?id=wechatpay-apiv3_wechatpay-java)
@@ -36,7 +36,7 @@
 在你的 build.gradle 文件中加入如下的依赖
 
 ```groovy
-implementation 'com.github.wechatpay-apiv3:wechatpay-java:0.2.14'
+implementation 'com.github.wechatpay-apiv3:wechatpay-java:0.2.15'
 ```
 
 #### Maven
@@ -47,7 +47,7 @@ implementation 'com.github.wechatpay-apiv3:wechatpay-java:0.2.14'
 <dependency>
   <groupId>com.github.wechatpay-apiv3</groupId>
   <artifactId>wechatpay-java</artifactId>
-  <version>0.2.14</version>
+  <version>0.2.15</version>
 </dependency>
 ```
 

gradle.properties

@@ -1,5 +1,5 @@
 projectPropGroup=com.github.wechatpay-apiv3
-projectPropVersion=0.2.14
+projectPropVersion=0.2.15
 
 slf4jVersion=1.7.36
 junitVersion=4.13.2