fix: dockerfile image build

[gcroci2]

While investigating issue #540, I encountered a problem with our Dockerfile build process. The root cause was a version mismatch with libstdc++.so.6, leading to the following error during a SciPy import:

libstdc++.so.6: version `GLIBCXX_3.4.29' not found

• The error occurred because the container was incorrectly linking to an outdated version of libstdc++.so.6 from the system's root directory, rather than the newer version available in the Conda environment.
• Although the required GLIBCXX_3.4.29 symbol was present in the Conda-managed version of libstdc++.so.6, the container failed to detect it and instead used the system's older version.

To resolve this, I made the following changes:

• Updated the base image: I changed the base image from ubuntu:20.04 to ubuntu:22.04, which includes a more recent version of libstdc++.so.6 in the system libraries.
• Manual Conda installation: instead of relying on the base image from Miniconda, I added the Conda installation steps directly in the Dockerfile taking inspiration from the original condaforge/miniforge3 image's Dockerfile.

These changes allow the container to correctly locate and use the updated libstdc++.so.6, resolving the build issue. Next steps are outlined in #529.

[github-actions]

This PR is stale because it has been open for 14 days with no activity.