Fix closing brace syntax in Dokka configuration (#403)

Author: zoobestik

build-logic/src/main/kotlin/kotlinx/io/conventions/kotlinx-io-dokka.gradle.kts

@@ -16,7 +16,7 @@ tasks.withType<AbstractDokkaTask>().configureEach {
         mapOf(
             "org.jetbrains.dokka.base.DokkaBase" to """{ "templatesDir" : "${
                 rootDir.resolve("dokka-templates")
-            }"""
+            }" }"""
         )
     )
 }