Switch back to upstream terser gem
We temporarily used a fork to get around a UTF-8 encoding issue with LICENSE (omnibus-gitlab#5716 (closed)), which was fixed in https://github.com/ahorek/terser-ruby/pull/6. We switch back to the upstream library now that this has been resolved.
This reverts some of the changes in !44961 (merged).
Full diff: https://github.com/ahorek/terser-ruby/compare/1.0.1..1.0.2
Edited by Stan Hu