chore: build and run Docker image with Eclipse Temurin 21 (#629)

Author: joschi

Dockerfile

@@ -1,9 +1,9 @@
-FROM openjdk:8-jdk-slim AS build
+FROM eclipse-temurin:21-jdk-alpine AS build
 WORKDIR /build
 COPY ./ /build
 RUN ./mvnw -V -B -ff -P docker package -q
 
-FROM openjdk:8-jre-slim
+FROM eclipse-temurin:21-jre-alpine
 WORKDIR /app
 COPY --from=build /build/cli/target/openapi-diff-cli-*-all.jar /app/openapi-diff.jar
 ENTRYPOINT ["java", "-jar", "/app/openapi-diff.jar"]