remove using __init__ by either using OncePerProcess or recomputing

[KristofferC]

__init__ is unfortunate in general because it requires unconditionally executing code on julia startup or package load and it also means the code cannot be pruned in e.g. trimming mode of julia. We can either use the new OncePerProcess to delay the execution until is needed or just skip the caching and recompute (the env_host_pattern_regex function is cheap enough that it shouldn't be an issue).

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 98.14%. Comparing base (8c93b06) to head (7a5bd22).
Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master      #39      +/-   ##
==========================================
- Coverage   99.23%   98.14%   -1.09%     
==========================================
  Files           4        3       -1     
  Lines         130      108      -22     
==========================================
- Hits          129      106      -23     
- Misses          1        2       +1     

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[StefanKarpinski]

I'm on board with this. Not sure maintaining support for older versions makes much sense for NetworkOptions. If we wanted to, you could metaprogram around the Julia version.

[visr]

Should be good to merge? And then BumpStdlibs to master and 1.12 so this and #37 are available for 1.12. Last time it ran was JuliaLang/julia#56949.