Fails for a multi-stage docker build

[Kushank24]

Is your feature request related to a problem? Please describe.
I tried to use dockerfile-image-update on a multi-stage build. The dockerfile I used was:

FROM openjdk:11 AS build
WORKDIR /app
COPY ./src ./src
RUN javac ./src/Main.java
FROM openjdk:11-jre-slim
WORKDIR /app
COPY --from=build /app/src/Main.class ./Main.class
CMD ["java", "Main"]

Now, when I ran the dockerfile-image update, it changed the jre also but that was not inteneded.
Describe the solution you'd like
The solution I suggest is to only look for base image instead of scanning the complete Dockerfile.

Additional context