ci: add RPM package generation

[ClementTsang]

Description

A description of the change, what it does, and why it was made. If relevant (such as any change that modifies the UI), please provide screenshots of the changes:

Issue

If applicable, what issue does this address?

Closes: #

Testing

If relevant, please state how this was tested. All changes must be tested to work:

Tested with nightly: https://github.com/ClementTsang/bottom/actions/runs/5263689619

Checklist

If relevant, ensure the following have been met:

• Areas your change affects have been linted using rustfmt (cargo fmt)
• The change has been tested and doesn't appear to cause any unintended breakage
• Documentation has been added/updated if needed (README.md, help menu, doc pages, etc.)
• The pull request passes the provided CI pipeline
• There are no merge conflicts
• If relevant, new tests were added (don't worry too much about coverage)

[codecov]

Codecov Report

Patch and project coverage have no change.

Comparison is base (2e5d59f) 31.61% compared to head (745c947) 31.61%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1206   +/-   ##
=======================================
  Coverage   31.61%   31.61%           
=======================================
  Files          97       97           
  Lines       16502    16502           
=======================================
  Hits         5217     5217           
  Misses      11285    11285           

Flag	Coverage Δ
macos-12	33.18% <ø> (ø)
ubuntu-latest	33.19% <ø> (ø)
windows-2019	33.43% <ø> (ø)

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