Add *.so and *.egg-info to gitignore

These are common generated files in Python projects and usually
ignored from version control.
3 jobs for ignore-common-python-build-files in 3 minutes and 1 second (queued for 2 seconds)
latest
Status Job ID Name Coverage
  Build
passed #698185
build-python27

00:01:51

passed #698186
build-python37

00:01:51

 
  Docs
passed #698187
docs

00:01:08