Fix hardcoded dependency on MSYS2.
Fix hardcoded dependency on MSYS2.

Ruby should be usable without MSYS2 on the target system.

larskanis/rubyinstaller2,larskanis/rubyinstaller2,larskanis/rubyinstaller2,oneclick/rubyinstaller2,oneclick/rubyinstaller2,oneclick/rubyinstaller2