Authentication integration test

- add end-to-end test AuthenticationEndpoint
- add user-token.data
- add admin-token.data
- add .data to .editorconfig

build.gradle.kts

@@ -8,6 +8,7 @@ plugins {
 }
 
 dependencies {
+    implementation(hlaeja.fasterxml.jackson.module.kotlin)
     implementation(hlaeja.kotlin.logging)
     implementation(hlaeja.kotlin.reflect)
     implementation(hlaeja.kotlinx.coroutines)