Update RMG developer install instruction

[oscarwumit]

Motivation or Problem

Run into several problems when doing a clean installation of RMG from source following the instructions recently. Turns out the guidance needs to be updated.

Description of Changes

1. set julia version to be 1.8.5, the latest version verified to work with current RMG. Newer julia versions such as 1.9.2 cause issues during compiling.

2. change the conda backend to classic/default before calling julia command; otherwise compilation won't complete.

3. update julia command so the package installation won't freeze.

Testing

Did a clean installation with the updated instruction. Ran RMG and Arkane minimal tests and they both work.

Reviewer Tips

Can try a clean installation to verify the changes.

[rwest]

Please can you put reasons for changes into the commit messages?
(A good general habit, not just here)
Thanks!

[codecov]

Codecov Report

Merging #2524 (96c8830) into main (32715ad) will not change coverage.
The diff coverage is n/a.

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  Misses      18613    18613           

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[rwest]

This CI run that on this PR that just failed used
julia 1.8.5 h783901f_0 conda-forge
The run on main last night that succeeded used
julia 1.9.2 hb81c242_0 conda-forge

I just created a new environment on my (Intel) Mac (with a new miniconda) and it worked fine with the libmamba solver, and with julia 1.9.2 h8d83f4a_0 conda-forge.

[oscarwumit]

Thanks for the comment. I will rebase and update the commit msg.

Regarding the Julia version and the solver backend. Yesterday I did a clean installation of RMG on an ubuntu 23.04 machine following the current instruction. However, using the libmamba solver in the Julia step will cause the installation to stall. I got an error msg saying things like "conda freeze when solving the environment, retrying with classic solver". However, the installation will just stay stalled and won't continue. When I switched to Julia 1.8.5 and used the classic solver, the installation worked fine.

I can try to do another fresh installation of RMG on an ubuntu machine to see if the issue persists.

[github-actions]

This pull request is being automatically marked as stale because it has not received any interaction in the last 90 days. Please leave a comment if this is still a relevant pull request, otherwise it will automatically be closed in 30 days.

[JacksonBurns]

The issues with Julia 1.9.2 seem to be resolved (see this successful CI run using that version), as well as the installation with mamba as the solver backend issue. I'll close this for the time being, but if we run into similar issues in the future we can pick this up.