�chore: dockerfile 수정

Dockerfile

@@ -1,17 +1,9 @@
-FROM gradle:jdk-21-and-22-alpine AS build
-WORKDIR /app
-
-COPY build.gradle settings.gradle /app/
-RUN gradle dependencies --no-daemon || return 0
-
-COPY . /app
-RUN gradle clean build --no-daemon -x test
-
 FROM openjdk:21-jdk-slim
-WORKDIR /app
 
-COPY --from=build /app/build/libs/*.jar /app/server.jar
+ARG JAR_FILE=./build/libs/*.jar
+
+COPY ${JAR_FILE} server.jar
 
 EXPOSE 8080
-ENTRYPOINT ["java"]
-CMD ["-jar", "server.jar"]
+
+ENTRYPOINT ["java", "-jar", "server.jar"]