Rebuild rdfind from another src rpm

I am currently using Oracle Linux 9 and could not find rdfind so decided to build it myself from the latest rpm I could find.

The build process is designed to run from a docker container to avoid contamination of the environment and also to allow this to be built on any PC/VM that can run docker.

Upstream source

see: https://github.com/pauldreik/rdfind

Steps to build

1. Requires docker to be installed
2. Create an empty PKGS directory with a non-root user to match the current user's UID.
3. Run: docker run -it -v $PWD:/build -w /build oraclelinux:9
4. From the container run: sh build
5. Any built rpms should be found in PKGS directory on builder box.

Notes

Configuration is a bit odd because I'm using an NFS mount and rootsquash is configured so writing files as root does not work. This slightly affects the build process.