Require Julia v1.6 and update CI setup

[giordano]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.24%. Comparing base (def2fd9) to head (fd7d08f).

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #13      +/-   ##
==========================================
+ Coverage   94.73%   98.24%   +3.50%     
==========================================
  Files           1        1              
  Lines          57       57              
==========================================
+ Hits           54       56       +2     
+ Misses          3        1       -2     

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[giordano]

There are various failures, but

OutputCollectors.jl: Test Failed at /Users/runner/work/OutputCollectors.jl/OutputCollectors.jl/test/runtests.jl:49
  Expression: output_str == stdout_msg * "\n" * stderr_msg * "\n"
   Evaluated: "Print to stderr\nPrint to stdout\n" == "Print to stdout\nPrint to stderr\n"
[...]
OutputCollectors.jl: Test Failed at /Users/runner/work/OutputCollectors.jl/OutputCollectors.jl/test/runtests.jl:50
  Expression: output_colored_str == stdout_msg * "\n" * red * stderr_msg * "\n" * default
   Evaluated: "\e[31mPrint to stderr\n\e[39mPrint to stdout\n" == "Print to stdout\n\e[31mPrint to stderr\n\e[39m"

Should these test that the output contains stderr/stdout separately, rather than in the specific order? Although I'm a bit surprised stderr comes before stdout given that the code is

OutputCollectors.jl/test/runtests.jl

Lines 38 to 43 in def2fd9

	stdout_msg = "Print to stdout"
	stderr_msg = "Print to stderr"
	cmd = """
	echo $(stdout_msg)
	echo $(stderr_msg) > /dev/stderr
	"""

[giordano]

This is still necessary on master (but tests are also failing....)