remove .github readme

[dougbrn]

Github repositories look first at the .github folder for README files to display on the repository home page. The recently added readme in .github by the PPT update is now overriding our main README file. This PR simply removes the PPT readme.

Made issue on PPT: lincc-frameworks/python-project-template#491

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 99.47%. Comparing base (12d1293) to head (2c4827e).
Report is 59 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #152   +/-   ##
=======================================
  Coverage   99.47%   99.47%           
=======================================
  Files          14       14           
  Lines         948      948           
=======================================
  Hits          943      943           
  Misses          5        5           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

Before [12d1293]	After [d2fba56]	Ratio	Benchmark (Parameter)
59.7±1ms	63.6±3ms	1.06	benchmarks.ReassignHalfOfNestedSeries.time_run
7.24±0.03ms	7.40±0.1ms	1.02	benchmarks.NestedFrameQuery.time_run
83.9M	83.8M	1	benchmarks.NestedFrameAddNested.peakmem_run
9.52±0.2ms	9.47±0.1ms	1	benchmarks.NestedFrameAddNested.time_run
90.8M	90.8M	1	benchmarks.NestedFrameQuery.peakmem_run
87.5M	87.4M	1	benchmarks.NestedFrameReduce.peakmem_run
258M	255M	0.99	benchmarks.AssignSingleDfToNestedSeries.peakmem_run
1.65±0.02ms	1.63±0.02ms	0.99	benchmarks.NestedFrameReduce.time_run
279M	277M	0.99	benchmarks.ReassignHalfOfNestedSeries.peakmem_run
31.3±1ms	29.9±1ms	0.95	benchmarks.AssignSingleDfToNestedSeries.time_run

Click here to view all benchmarks.