Minor updates to the porting readme

[rogurr]

Ran through the porting steps on a clean WSL and found a few minor corrections to the documentation.

[Javagedes]

Hi @rogurr, this is great; thank you! There is currently a markdown issue outside of your change. I'm going to get that fixed and then get your PR merged.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.71%. Comparing base (bf643b0) to head (2e11c3f).
Report is 102 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #881      +/-   ##
==========================================
- Coverage   78.75%   78.71%   -0.05%     
==========================================
  Files          49       41       -8     
  Lines        4909     5050     +141     
==========================================
+ Hits         3866     3975     +109     
- Misses       1043     1075      +32     

see 49 files with indirect coverage changes