Fix dockerfile for new changes

Dockerfile

@@ -1,28 +1,18 @@
-# Adapted from: https://github.com/PaperMC/bibliothek/blob/063cc014193b6ea160b3cabc7b93f70009e1fb2a/Dockerfile
-ARG JAVA_VERSION=17
-ARG JVM_FLAVOR=hotspot
-
-FROM eclipse-temurin:${JAVA_VERSION}-jdk-alpine AS builder
-WORKDIR /build
-
-COPY ./ ./
-RUN ./gradlew clean buildForDocker --no-daemon
-
-
-ARG JAVA_VERSION
-ARG JVM_FLAVOR
-
-FROM eclipse-temurin:${JAVA_VERSION}-alpine
-WORKDIR /app
+FROM eclipse-temurin:17-alpine
 
 # Install curl for the healthcheck
 RUN apk update && apk add curl
 
 RUN addgroup -S pingapi \
     && adduser -S pingapi -G pingapi \
-    && chown -R pingapi:pingapi /app
+    && chown -R pingapi:pingapi /opt/app
 USER pingapi:pingapi
 
+WORKDIR /opt/app
+
+COPY build/libs/ServerPingApi.jar ServerPingApi.jar
+COPY ./docker/default.application.yaml ./default.application.yaml
+
 EXPOSE 8080
 
 # We override default config location search path,
@@ -31,7 +21,6 @@ EXPOSE 8080
 # but they take precedence over config file
 # https://docs.spring.io/spring-boot/docs/1.5.6.RELEASE/reference/html/boot-features-external-config.html
 ENV SPRING_CONFIG_LOCATION="optional:classpath:/,optional:classpath:/config/,file:./default.application.yaml,optional:file:./,optional:file:./config/"
-COPY ./docker/default.application.yaml ./default.application.yaml
 
 HEALTHCHECK --interval=30s --timeout=30s --start-period=5s \
     --retries=3 CMD [ "sh", "-c", "echo -n 'curl localhost:8080... '; \
@@ -41,5 +30,5 @@ HEALTHCHECK --interval=30s --timeout=30s --start-period=5s \
         echo Fail && exit 2\
     )"]
 
-COPY --from=builder /build/build/libs/docker/serverpingapi.jar ./
-CMD ["java", "-jar", "/app/serverpingapi.jar"]
+
+CMD ["java", "-jar", "ServerPingApi.jar"]