ci: Simple/mechanical tweaks to config file

Got rid of long lines in favor of more lines for readability. Cleaned up
some comments/typos and unnecessary cruft*. Finally ran prettier on the
file for its automatic formatting, including whitespace clean ups.

cruft:

-  && when already set -e
- run commands with trailing \
- deleted commented out "OLD STUFF"
- sorted listy looking things because unsorted stuff bothers me :) (I
  held back on sorting the board build definitions though, thats
  probably too much).

Signed-off-by: Manuel Mendez <[email protected]>
Signed-off-by: Thierry Laurion <[email protected]>