Fix Sucrase build script
Fix Sucrase build script

We forgot to tell it to build TSX, so it's been failing to build & instead erroring out.

xfix/Pokemon-Showdown,svivian/Pokemon-Showdown,xfix/Pokemon-Showdown,svivian/Pokemon-Showdown,svivian/Pokemon-Showdown,svivian/Pokemon-Showdown,svivian/Pokemon-Showdown,xfix/Pokemon-Showdown,xfix/Pokemon-Showdown,xfix/Pokemon-Showdown