refactor(logger): remove LoggerUtil and add simplelogger for tests

gradle/libs.versions.toml

@@ -13,6 +13,7 @@ cutin = "0.1.1-cad019e"
 [libraries]
 junit-jupiter = { module = "org.junit.jupiter:junit-jupiter", version.ref = "junit-jupiter" }
 slf4j = { module = "org.slf4j:slf4j-api", version.ref = "slf4j"}
+slf4j-simple = { module = "org.slf4j:slf4j-simple", version.ref = "slf4j"}
 javacord = { module = "org.javacord:javacord", version.ref = "javacord"}
 discord4j = { module = "com.discord4j:discord4j-core", version.ref = "discord4j"}
 geantyref = { module = "io.leangen.geantyref:geantyref", version.ref = "geantyref"}