Add JET workflow

[kimikage]

This is the workflow (GitHub Actions) version of PR #324.

CC: @PatrickHaecker

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.22%. Comparing base (6decae1) to head (ca203be).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #358   +/-   ##
=======================================
  Coverage   97.22%   97.22%           
=======================================
  Files           7        7           
  Lines         792      792           
=======================================
  Hits          770      770           
  Misses         22       22           

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[PatrickHaecker]

I recommend to implement the two suggested changes. The PR otherwise looks good to me.

[PatrickHaecker]

Suggested change

	run: julia --project=. --color=yes -e '
	using JET, Test;
	using FixedPointNumbers;
	println("report_package(FixedPointNumbers, toplevel_logger=nothing)");
	show(JET.report_package(FixedPointNumbers, toplevel_logger=nothing));
	@testset "JET" begin
	JET.test_package(FixedPointNumbers; target_modules=(FixedPointNumbers,));
	end'
	run: |
	julia --project=. --color=yes -e '
	using JET, Test, FixedPointNumbers
	@testset "JET" begin
	JET.test_package(FixedPointNumbers; target_modules=(FixedPointNumbers,))
	end'

report_package analyzes the package a second time. Without target_modules, it also lists reports from other modules, and those do not affect the result. When test_package fails, it already prints the reports that caused the failure.

The | block, keeps the newlines, so no trailing semicolons are needed improving readability.

[kimikage]

I thought it might be helpful to include potential issues as reference information.
If you feel it's annoying, I'll remove it.