Add duplicates strategy to build file to be gradle v7 compatible

roles/keycloak/files/providers/keycloak-mailpass-rest/build.gradle.kts

@@ -51,6 +51,7 @@ dependencies {
 
 tasks {
     jar {
+        duplicatesStrategy = DuplicatesStrategy.INCLUDE
         from(configurations.runtimeClasspath.get().map { if (it.isDirectory) it else zipTree(it) }) {
             exclude("META-INF/MANIFEST.MF")
             exclude("META-INF/*.SF")