I'm running podman 3.4.4 on Ubuntu 22.04 LTS server.

I have been having `podman build` issues that are not reproducible if I do those steps after the container build using `podman run`.

Eventually I traced it to this: the limits given to processes in `podman build` are completely different. Here's a sample Dockerfile:

```
FROM node:14-bullseye
WORKDIR /app
RUN echo "clear cache 1"
RUN bash -c 'cat /proc/$$/limits'
# Placeholder, not used in this example
CMD bash
```

If I run:

```
podman build -t project .
```

This prints (among other things):

```
Max open files            1024                 1024                 files     
```

Gee, that's low.

If I run it again as root and use `ulimit -n 131072`, then `cat /proc/self/limits` shows my increased limit. But if I then bump "Clear cache 1" to "Clear cache 2" in the Dockerfile (**this is important**) and run the build command, still in that root shell with the increased ulimit, I still get:

```
Max open files            1024                 1024                 files     
```

So that's what I see in `podman build`. However if I then open a bash shell in a container using the new image using `podman run`, I get this result:

```
root@ubuntu:/home/ubuntu/opt/cloud/build# podman run -it project bash
root@17961323a1c9:/app# cat /proc/$$/limits
Max open files            1048576              1048576              files     
```

The command has completely different results at build time and at "run" time.

I did try to modify `ulimit` inside a RUN command, but no dice:

```
bash: line 1: ulimit: open files: cannot modify limit: Operation not permitted
Error: error building at STEP "RUN bash -c 'ulimit -n 131072 && cat /proc/$$/lim
```

Anyway it would be much better to increase this for the build command in general, or at least using an option to it, rather than for every command.

Practically speaking this appears to be behind a build failure I have with a larger Dockerfile, but I've boiled it down to this straightforward test case.

I have also tried using `docker` (real Docker Engine). The problem does not happen with Docker Engine, I get 1048576 files there during build.

How can I increase the file descriptor limit at build time?

Thank you!