[RSDK-6152] Downgrade build image requirement

[njooma]

We need to use a build image that is less than ubuntu:22.04. Currently the only image that is greater than that is for aarch64.

This PR makes the aarch64 build image ubuntu:20.04. (The other linux architectures are centos:7)

[njooma]

The working build can be found here: https://github.com/viamrobotics/rust-utils/actions/runs/7479772459

The built library was tested against debian:bullseye, and everything is working!

With the current distribution: OSError: /lib/aarch64-linux-gnu/libc.so.6: version GLIBC_2.32' not found (required by /usr/local/lib/python3.9/dist-packages/viam/rpc/libviam_rust_utils.so)`

With this library built from this PR:

2024-01-10 19:15:49,927		INFO	viam.rpc.dial (dial.py:286)	Connecting to socket: /tmp/proxy-XsCd8Ujw.sock	
Resources:
[<viam.proto.common.ResourceName rdk:service:sensors/builtin at 0xffff8ecdf3b0>, <viam.proto.common.ResourceName rdk:service:motion/builtin at 0xffff8ef915e0>, <viam.proto.common.ResourceName rdk:service:data_manager/builtin at 0xffff8fea98b0>, <viam.proto.common.ResourceName rdk:component:board/board at 0xffff8ecf4db0>]
board gpio_pin_by_name return value: <viam.components.board.client.GPIOPinClient object at 0xffff8d10d1f0>

[benjirewis]

Do you want to rerelease rust-utils after this @njooma?

[benjirewis]

Nice; smart to put the runs-on in the matrix variables! 🧑‍🔧 .

[njooma]

Do you want to rerelease rust-utils after this @njooma?

Yup, I'll do a release this afternoon and get a python prerelease out today as well