Migrate to condaforge/linux-anvil base image

[idigs]

Proposal to use linux-anvil-x86_64:alma9 in lieu of current solution.

Inherit from condaforge Anvil

FROM docker.io/condaforge/linux-anvil-x86_64:alma9

• https://github.com/conda-forge/docker-images/blob/main/linux-anvil/Dockerfile
• miniforge comes pre-installed on container image
  • miniforge version=24.7.1-2
  • no mechanism for automatically tracking upstream changes to miniforge
  • miniforge install handled by https://github.com/conda-forge/docker-images/blob/main/scripts/run_commands

-> Do we have the ability to bump miniforge version that's baked into container?
-> How inclusive is the https://github.com/conda-forge/docker-images project to new contributors?

VS

"Roll Your Own" (currently used method)

FROM almalinux:9
RUN dnf -y install_a_bunch_of_stuff

• miniforge installed as part of jenkins pipeline
  • miniforge version 24.11.3-0
  • miniforge install handled by https://github.com/mantidproject/mantid/blob/main/buildconfig/Jenkins/Conda/download-and-install-miniforge

• drawbacks include longer build times b/c miniforge is installed all over again for each workflow instance
• benefits include complete autonomy over miniforge version being installed

[thomashampson]

I think we should move away from miniforge, and attempt to use pixi for all of the conda environments that are used in our build scripts.