Update README to be clear that git v2.28 or later is needed (to support git init -b)

[gherlein]

I stupidly missed the git init step on an Ubuntu 20.10 EC2 instance (quite a common instance type) and was confused when git init -b failed. Updating the readme to hopefully help someone else.

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[codecov-commenter]

Codecov Report

Merging #1424 (9927d2a) into main (d90284c) will decrease coverage by 0.05%.
The diff coverage is 94.16%.

@@            Coverage Diff             @@
##             main    #1424      +/-   ##
==========================================
- Coverage   88.06%   88.00%   -0.06%     
==========================================
  Files         132      134       +2     
  Lines        5109     5144      +35     
  Branches     1207     1194      -13     
==========================================
+ Hits         4499     4527      +28     
- Misses        610      617       +7     

Impacted Files	Coverage Δ
src/awscdk/cdk-config.ts	100.00% <ø> (ø)
src/cdk/consts.ts	100.00% <ø> (+36.36%)	⬆️
src/github/github-project.ts	100.00% <ø> (ø)
src/javascript/node-project.ts	81.38% <83.33%> (-2.05%)	⬇️
src/javascript/prettier.ts	85.71% <85.71%> (ø)
src/awscdk/awscdk-app-ts.ts	92.53% <100.00%> (ø)
src/awscdk/cdk-tasks.ts	100.00% <100.00%> (ø)
src/build/build-workflow.ts	94.73% <100.00%> (-0.79%)	⬇️
src/cdk/jsii-project.ts	92.07% <100.00%> (-0.23%)	⬇️
src/github/auto-approve.ts	100.00% <100.00%> (ø)
... and 15 more

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[Chriscbr]

and was confused when git init -b failed

I think it might be possible to fix this directly instead to save future users' pain:

projen/src/cli/cmds/new.ts

Line 248 in 09e8ece

git('init -b main');

What if we run git init followed by git branch -m main instead?

[gherlein]

That would probably be better, since Ubuntu 20.04 is LTS and will be a very common platform for many

[eladb]

Ooouch. Would it make more sense to check the git version and use the previous set of commands as a fallback?

[gherlein]

That's even better. Maybe with a note to the user "older version of git found, using fallback command list; please consider upgrading to a version of git >= 2.28" or something like that

[gherlein]

I'll submit a new PR with a fix