disable this-escape warning for tests

Author: laurit

buildSrc/src/main/kotlin/otel.java-conventions.gradle.kts

@@ -60,6 +60,7 @@ tasks {
       if (name.contains("Test")) {
         // serialVersionUI is basically guaranteed to be useless in tests
         compilerArgs.add("-Xlint:-serial")
+        compilerArgs.add("-Xlint:-this-escape")
       }
     }
   }