Required Socket Files Ignored

[ginadi011]

Actual behavior
I am building a Docker image which has MIMEDefang and Postfix, both of which require Unix socket to run as expected. Kaniko is ignoring the socket files which prevent the applications from running as expected.

Expected behavior
Required socket files are added into the Docker image after image is built

To Reproduce
Steps to reproduce the behavior:

1. Build image

Additional Information

• Dockerfile
  ` FROM

RUN yum -y install mimedefang

RUN yum install -y postfix

RUN ./usr/bin/mimedefang-multiplexor -m 4 -x 10 -y 0 -U defang -l -d -s /var/spool/MIMEDefang/mimedefang-multiplexor.sock
RUN ./usr/bin/mimedefang -m /var/spool/MIMEDefang/mimedefang-multiplexor.sock -y -U defang -q -T -p inet:10997
RUN ./usr/bin/mimedefang-multiplexor -U defang -o /var/spool/MIMEDefang/mimedefang-multiplexor.lock

RUN ./usr/bin/mimedefang -P /run/mimedefang.pid -o /var/spool/MIMEDefang/mimedefang.lock -m /var/spool/MIMEDefang/mimedefang-multiplexor.sock -y -R -1 -U defang -T -G -q -p /var/spool/MIMEDefang/mimedefang.sock

RUN ./usr/libexec/mimedefang-wrapper -U defang start
RUN ./usr/libexec/mimedefang-wrapper -U defang multiplexor

CMD ["postfix start-fg"]`

Triage Notes for the Maintainers

Description	Yes/No
Please check if this a new feature you are proposing	- [ No]
Please check if the build works in docker but not in kaniko	- [ Yes]
Please check if this error is seen when you use --cache flag	- [Yes ]
Please check if your dockerfile is a multistage dockerfile	- [No ]