Fix a typo in the activation script

[Earlopain]

I for sure thought it would change meaning but turns out this space doesn't matter and the ast is the same.

[andyw8]

Interesting!

irb(main):010> defined?(RubyVM::YJIT)
=> "constant"
irb(main):011> defined?(RubyVM:: YJIT)
=> "constant"
irb(main):012> defined?(RubyVM ::YJIT)
=> nil
irb(main):013> defined?(RubyVM :: YJIT)
=> nil

[Earlopain]

You can add as many spaces to the right as you want. Might be a ruby bug, not sure, defined? is pretty weird.

[Earlopain]

Oh. You can also just do this:

RubyVM:: YJIT
=> RubyVM::YJIT

So, not the fault of defined? and probably intended and/or for backwards compatibility.