Update README.md

Author: ivolz

README.md

@@ -11,7 +11,7 @@ The Approov integration is available via [`maven`](https://mvnrepository.com/rep
 The `Maven` repository is already present in the gradle.build file so the only import you need to make is the actual service layer itself:
 
 ```
-implementation("io.approov:service.httpsurlconn:3.5.1")
+implementation("io.approov:service.httpsurlconn:3.5.3")
 ```
 
 Make sure you do a Gradle sync (by selecting `Sync Now` in the banner at the top of the modified `.gradle` file) after making these changes.