gradle: Remove support for unsigned integers

build.gradle

@@ -70,7 +70,6 @@ allprojects {
         // Warnings are potential errors, so stop ignoring them
         // You can override by passing `-PallWarningsAsErrors=false` in the command line
         kotlinOptions.allWarningsAsErrors = project.getProperties().getOrDefault("allWarningsAsErrors", "true").toBoolean()
-        kotlinOptions.freeCompilerArgs += "-Xopt-in=kotlin.ExperimentalUnsignedTypes"
     }
 }