Fix return value type for IO#wait_writable

[koic]

IO#wait_writable does not return bool unlike IO#wait_readable.
https://docs.ruby-lang.org/en/3.1/IO.html#method-i-wait_writable

[soutaro]

Let me confirm:

1. This is the fix of method type, which is not changed since Ruby 3.1.1, and
2. [ruby/io-wait] [DOC] Fix the return values #942 is the fix of document, which is changed since Ruby 3.1.1

RBS is based on the latest release of Ruby, 3.1.1 as of today. So, I will merge this, but won't #942.

Does it make sense?

[koic]

2. [ruby/io-wait] [DOC] Fix the return values #942 is the fix of document, which is changed since Ruby 3.1.1

RBS is based on the latest release of Ruby, 3.1.1 as of today. So, I will merge this, but won't #942.

I don't have a strong opinion. OTOH, ruby/io-wait seems to be able to bundle update independently of the Ruby versions. So, I think it is possible to fix the document independently of Ruby 3.1.1.
ruby/io-wait@d0721e300a

Either way, that's just my point of view, and I'll leave the decision to the maintainers anyway. Thank you for your maintenance.

[soutaro]

ruby/io-wait seems to be able to bundle update independently of the Ruby versions

Ah... it totally makes sense...
Yes, it's the problem of having gems in stdlib directory. So, let me leave it for now.

So, we will update the type now, but will update the doc later. Thanks again! 🙏