Partial image rebuilds

[kwabenantim]

Summary

Consider adding a github workflow to update a single dependency in a docker image without rebuilding everything else. Currently, all dependencies in an image need to be rebuilt, even when only one dependency is being updated.

For example if we only want to change the version of PETSc in the portability-dev image, the workflow should:

• Remove the old PETSc version from the current portability-dev image.
• Build the new PETSc version into the image.
• Keep all the other dependencies in place.

[kwabenantim]

As some packages depend on other custom built packages, this would still require rebuilding multiple packages in some instances. For example, rebuilding HDF5 would require rebuilding VTK and possibly PETSc.

Because of these inter-relationships, it might be simpler to rebuild everything to make sure that they all still work with one other.