Add fiddle as a dependency?

[st0012]

Description

From this issue's description, it looks like reline relies on fiddle (probably since 74a7ffa). But because fiddle is not a required dependency of reline, it could cause issues like:

(backtrace taken from the original issue)

 /usr/local/bundle/gems/bootsnap-1.8.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `require': cannot load such file -- fiddle (LoadError)
from /usr/local/bundle/gems/bootsnap-1.8.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:23:in `block in require_with_bootsnap_lfi'
from /usr/local/bundle/gems/bootsnap-1.8.1/lib/bootsnap/load_path_cache/loaded_features_index.rb:89:in `register'
from /usr/local/bundle/gems/bootsnap-1.8.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:22:in `require_with_bootsnap_lfi'
from /usr/local/bundle/gems/bootsnap-1.8.1/lib/bootsnap/load_path_cache/core_ext/kernel_require.rb:44:in `require'
from /usr/local/bundle/gems/zeitwerk-2.5.0.beta3/lib/zeitwerk/kernel.rb:35:in `require'
from /usr/local/bundle/gems/reline-0.2.7/lib/reline/terminfo.rb:1:in `<main>'

So maybe fiddle should be declared as a dependency?

[aycabta]

If libffi is not included on your system, fiddle gem installation will fail, so irb gem as a default gem cannot depend on fiddle gem.

[st0012]

@aycabta ah I see. thanks for the explanation!

[aycabta]

However, crashing is pretty bad, so I took measures to prevent it by #378.

[st0012]

@aycabta thanks again!