Fix broken test "test_compilation_error"

[wwood]

Hi there,

I'm in the process of packaging ruby-coffee-script for GNU Guix, and I came across this failing test. Seemed easy enough to fix, so here it is.

Beforehand:

Run options: --seed 49250

# Running:

..F....

Finished in 0.107786s, 64.9436 runs/s, 102.0542 assertions/s.

  1) Failure:
TestCoffeeScript#test_compilation_error [/tmp/nix-build-ruby-coffee-script-2.4.1.drv-0/ruby-coffee-script-2.4.1/test/test_coffee_script.rb:70]:
message was "[stdin]:3:11: unexpected unless"

[rails-bot]

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[wwood]

So, upon further reflection, it isn't immediately obvious to me why it was failing in the first place. Here's the gems I have loaded. Perhaps because I am using duktape and not rubyracer? I am not sure, perhaps you know better.

bigdecimal (1.2.6)
coffee-script-source (1.10.0)
duktape (1.3.0.4)
execjs (2.6.0)
io-console (0.4.3)
json (1.8.1)
minitest (5.4.3)
power_assert (0.2.2)
psych (2.0.8)
rake (10.4.2)
rdoc (4.2.0)
test-unit (3.0.8)