Upgrade to sinatra v2.1.0

[sue445]

sinatra v2.0.x doesn't work on ruby 3.0

/home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/mustermann-1.1.1/lib/mustermann.rb:73:in `new': Hash can't be coerced into Mustermann::Pattern (TypeError)
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/mustermann-1.1.1/lib/mustermann.rb:70:in `block in new'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/mustermann-1.1.1/lib/mustermann.rb:70:in `map'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/mustermann-1.1.1/lib/mustermann.rb:70:in `new'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:1641:in `compile'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:1629:in `compile!'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:1271:in `error'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:1831:in `<class:Base>'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:889:in `<module:Sinatra>'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/base.rb:22:in `<top (required)>'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/main.rb:26:in `<module:Sinatra>'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra/main.rb:1:in `<top (required)>'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/sinatra-2.0.7/lib/sinatra.rb:1:in `<top (required)>'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from <internal:/home/deploy/local/ruby/lib/ruby/3.0.0/rubygems/core_ext/kernel_require.rb>:85:in `require'
        from /home/deploy/local/ruby/lib/ruby/gems/3.0.0/gems/stackprof-webnav-1.0.2/lib/stackprof-webnav/server.rb:1:in `<top (required)>'

This problem is resolved at sinatra v2.1.0

ref.

• https://github.com/sinatra/sinatra/blob/master/CHANGELOG.md#210--2020-09-05
• Fix additional Ruby 2.7 keyword warnings sinatra/sinatra#1586
• eliminate warnings of keyword parameter for ruby 2.7.0 sinatra/sinatra#1581

So I want to upgrade.