Difficulties in installing asciidoctor-pdf

ruby --version
ruby 3.0.1p64 (2021-04-05 revision 0fb782ee38) [x86_64-linux]

bundle --version
Bundler version 2.2.17

$ bundle config set --local path .bundle/gems && bundle
Fetching https://github.com/prawnpdf/prawn.git
Fetching https://github.com/prawnpdf/prawn-table.git
Fetching gem metadata from https://rubygems.org/..........
Resolving dependencies...
Bundler could not find compatible versions for gem "prawn":
  In Gemfile:
    prawn

    asciidoctor-pdf was resolved to 1.5.0.alpha.7, which depends on
      prawn (= 1.2.1)

    prawn-table was resolved to 0.2.3, which depends on
      prawn (>= 1.3.0, < 3.0.0)

Bundler could not find compatible versions for gem "prawn-table":
  In Gemfile:
    prawn-table

    asciidoctor-pdf was resolved to 1.5.0.alpha.8, which depends on
      prawn-table (= 0.2.1)

Am I worng to assume there's a Gemfile created right? Can you try updating the dependencies to latests? Alpha's are quite old, a normal gem install should resolve to 1.5.4 (no alpha or beta).

Thank you much. It works. I could install it without problems.

What I find good is that it is how I have read it, a standalone PDF producer, and I liked the default formatting.

I have noticed that this character does not produce: ☎, does it mean that Unicode is not supported, or I maybe lack some fonts?

I have noticed that the author, date is not appearing visually in the output of the Asciidoctor PDF. Is it intentional?