fluidnumerics-self: new package

[fluidnumerics-joe]

This PR adds a new package : FluidNumerics/SELF (the Spectral Element Library in Fortran)

[spackbot-app]

@fluidnumerics_joe @garrettbyrd can you review this PR?

This PR modifies the following package(s), for which you are listed as a maintainer:

• self

[alalazo]

LGTM. Just a question

[alalazo]

@spackbot fix style

[spackbot-app]

Let me see if I can fix that for you!

[spackbot-app]

I was able to run spack style --fix for you!

spack style --fix

==> Running style checks on spack
  selected: import, isort, black, flake8, mypy
==> Modified files
  var/spack/repos/builtin/packages/fluidnumerics-self/package.py
==> Running import checks
import check requires Python 3.9 or later
  import checks were clean
==> Running isort checks
  isort checks were clean
==> Running black checks
reformatted var/spack/repos/builtin/packages/fluidnumerics-self/package.py
All done! ✨ 🍰 ✨
1 file reformatted.
  black checks were clean
==> Running flake8 checks
  flake8 checks were clean
==> Running mypy checks
lib/spack/spack/version/version_types.py:134: error: Incompatible types in assignment (expression has type "Tuple[Any, ...]", variable has type "Tuple[str]")  [assignment]
lib/spack/spack/variant.py:130: error: Unsupported right operand type for in ("Union[Collection[Any], Callable[..., Any]]")  [operator]
lib/spack/spack/build_environment.py:171: error: Overloaded function signatures 1 and 2 overlap with incompatible return types  [misc]
lib/spack/spack/build_environment.py:171: error: Overloaded function signatures 1 and 3 overlap with incompatible return types  [misc]
Found 4 errors in 3 files (checked 636 source files)
  mypy found errors

Keep in mind that I cannot fix your flake8 or mypy errors, so if you have any you'll need to fix them and update the pull request. If I was able to push to your branch, if you make further changes you will need to pull from your updated branch before pushing again.

I've updated the branch with style fixes.