Opt-in for MFA requirement explicitly

[tagliala]

As a popular gem (over 180 million total downloads), ethon implicitly requires that all privileged operations by any of the owners require OTP.

By explicitly setting rubygems_mfa_required metadata, the gem will show "NEW VERSIONS REQUIRE MFA" and "VERSION PUBLISHED WITH MFA" in the sidebar at https://rubygems.org/gems/ethon

This commit also introduces additional metadata

Ref:

• https://blog.rubygems.org/2022/08/15/requiring-mfa-on-popular-gems.html
• https://guides.rubygems.org/mfa-requirement-opt-in/

---

metadata verified via

$ gem build
$ gem spec -l ethon-0.17.0.gem 

# ...
metadata:
  bug_tracker_uri: https://github.com/typhoeus/ethon/issues
  changelog_uri: https://github.com/typhoeus/ethon/blob/v0.17.0/CHANGELOG.md
  documentation_uri: https://www.rubydoc.info/gems/ethon/0.17.0
  rubygems_mfa_required: 'true'
  source_code_uri: https://github.com/typhoeus/ethon/tree/v0.17.0
# ...

[tagliala]

Failure is unrelated

-- Control frame information -----------------------------------------------
c:0009 p:---- s:0050 e:000049 CFUNC  :easy_cleanup
c:0008 p:---- s:0047 e:000046 CFUNC  :call
c:0007 p:0007 s:0042 e:000041 METHOD /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/ffi-1.17.2/lib/ffi/autopointer.rb:152
c:0006 p:0016 s:0037 e:000036 METHOD /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/ffi-1.17.2/lib/ffi/autopointer.rb:143 [FINISH]
c:0005 p:0114 s:0032 e:000031 METHOD /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/webrick-1.9.1/lib/webrick/httpresponse.rb:135
c:0004 p:0011 s:0027 e:000025 METHOD /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/webrick-1.9.1/lib/webrick/httpserver.rb:238
c:0003 p:0018 s:0021 e:000020 METHOD /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/webrick-1.9.1/lib/webrick/httpserver.rb:72
c:0002 p:0106 s:0009 e:000008 BLOCK  /home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/webrick-1.9.1/lib/webrick/server.rb:310 [FINISH]
c:0001 p:---- s:0003 e:000002 DUMMY  [FINISH]

-- Ruby level backtrace information ----------------------------------------
/home/runner/work/ethon/ethon/vendor/bundle/ruby/3.5.0+3/gems/webrick-1.9.1/lib/webrick/server.rb:310:in 'block in start_thread'

[felipedmesquita]

🎉 thanks!