simplify .ms heuristic (#4224)
simplify .ms heuristic (#4224)

Simplify .ms heuristic for Unix Assembly by just checking that there is no
`/*` string in the file. This is simpler and seems to work with all Unix Assembly
files in GitHub. A synthetic MAXScript file was also tested by adding assembly inside
a multiline comment.
erkyrath/linguist,github/linguist,sebgod/linguist,sebgod/linguist,github/linguist,pchaigno/linguist,christop/linguist,erkyrath/linguist,erkyrath/linguist,erkyrath/linguist,github/linguist,sebgod/linguist,christop/linguist,pchaigno/linguist,github/linguist,sebgod/linguist,pchaigno/linguist,pchaigno/linguist