Add missing arguments to run_process

[A5rocks]

Fixes #3183

I tried out TypedDict here like @decorator-factory recommended and it's nicer, though it's explicitly trading off user experience:

• no defaults listed
• wacky reveal_type at least under mypy

I think it's worth it? I doubt people are looking at overloads for the defaults to things.

I still need to add type tests.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 100.00000%. Comparing base (d63f3a9) to head (d82d545).
Report is 3 commits behind head on main.

Additional details and impacted files

@@               Coverage Diff               @@
##                 main        #3212   +/-   ##
===============================================
  Coverage   100.00000%   100.00000%           
===============================================
  Files             124          124           
  Lines           18764        18771    +7     
  Branches         1269         1269           
===============================================
+ Hits            18764        18771    +7     

Files with missing lines	Coverage Δ
src/trio/_subprocess.py	100.00000% <100.00000%> (ø)

[jakkdl]

I haven't looked terribly close at the arguments, but seems fine at a glance.
In an ideal world it'd maybe be nice to have tests.. but it sounds messy to write something that validates against typeshed signatures and handles version/platform differences.