feat(logging): replace log4j dependency with slf4j and replace imports

wrapper/javacord/build.gradle.kts

@@ -21,7 +21,7 @@ dependencies {
     testImplementation(libs.mockito)
 
     testRuntimeOnly("org.junit.platform:junit-platform-launcher")
-    implementation(libs.log4j)
+    implementation(libs.slf4j)
     implementation(libs.javacord)
     implementation(libs.geantyref)
     implementation(project(":lib"))

wrapper/javacord/src/main/java/net/tomatentum/marinara/wrapper/javacord/JavacordWrapper.java

@@ -1,8 +1,8 @@
 package net.tomatentum.marinara.wrapper.javacord;
 
-import org.apache.logging.log4j.Logger;
 import org.javacord.api.DiscordApi;
 import org.javacord.api.interaction.SlashCommandBuilder;
+import org.slf4j.Logger;
 
 import net.tomatentum.marinara.wrapper.CommandConverter;
 import net.tomatentum.marinara.wrapper.CommandRegisterer;