docs: update version

Author: Magnet-js

README.md

@@ -14,15 +14,15 @@ We provide our Plugin SDK via Maven Central Repository (https://repo1.maven.org/
 <dependency>
     <groupId>com.staffbase</groupId>
     <artifactId>plugins-sdk-java</artifactId>
-    <version>1.2.4</version>
+    <version>1.2.9</version>
 </dependency>
 ```
 
 ### Gradle
 
 ```
 dependencies {
-    compile 'com.staffbase:plugins-sdk-java:1.2.3'
+    compile 'com.staffbase:plugins-sdk-java:1.2.9'
 }
 ```