Update build_ngx_pagespeed_from_source.html (#1707)
Update build_ngx_pagespeed_from_source.html (#1707)

Update to the build description work after the repo transfer

Fixes https://github.com/apache/incubator-pagespeed-ngx/issues/1524
pagespeed/mod_pagespeed,pagespeed/mod_pagespeed,pagespeed/mod_pagespeed,pagespeed/mod_pagespeed,pagespeed/mod_pagespeed,pagespeed/mod_pagespeed,pagespeed/mod_pagespeed