codespaces: revert config workaround

[pmrowla]

Codespaces git install appears to be fixed now, both github /usr/local/bin/git and system /usr/bin/git use /etc/gitconfig in the latest codespaces container
Closes #148

[codecov-commenter]

Codecov Report

Base: 81.65% // Head: 79.89% // Decreases project coverage by -1.76% ⚠️

Coverage data is based on head (761d321) compared to base (339fdba).
Patch coverage: 84.61% of modified lines in pull request are covered.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #174      +/-   ##
==========================================
- Coverage   81.65%   79.89%   -1.76%     
==========================================
  Files          25       25              
  Lines        3412     3383      -29     
  Branches      588      583       -5     
==========================================
- Hits         2786     2703      -83     
- Misses        544      590      +46     
- Partials       82       90       +8     

Impacted Files	Coverage Δ
src/scmrepo/git/backend/dulwich/credentials.py	25.22% <0.00%> (ø)
src/scmrepo/git/backend/gitpython.py	63.44% <0.00%> (-1.08%)	⬇️
src/scmrepo/git/backend/dulwich/__init__.py	79.67% <61.53%> (+0.53%)	⬆️
src/scmrepo/fs.py	61.39% <75.00%> (ø)
src/scmrepo/git/backend/pygit2.py	77.37% <90.00%> (+0.83%)	⬆️
src/scmrepo/git/__init__.py	83.05% <100.00%> (-1.00%)	⬇️
src/scmrepo/git/backend/base.py	80.88% <100.00%> (ø)
src/scmrepo/git/backend/dulwich/asyncssh_vendor.py	78.20% <100.00%> (-5.13%)	⬇️
src/scmrepo/git/backend/dulwich/client.py	62.50% <100.00%> (ø)
src/scmrepo/git/stash.py	83.33% <100.00%> (ø)
... and 15 more

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.