Drop Ruby 3.2 from Rails edge test matrix

[tagliala]

Rails edge currently requires Ruby >= 3.3(.1), so testing against Ruby 3.2 no longer reflects a supported combination.

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Ref:

• https://github.com/rails/rails/blob/4aafd831a6e4c2979e43a4069f1415860d6ffc1e/rails.gemspec#L12
• https://github.com/roidrage/lograge/actions/runs/28880833217/job/85668282950

  Because every version of activerecord depends on Ruby >= 3.3.1
    and rails_edge.gemfile depends on activerecord >= 0,
    Ruby >= 3.3.1 is required.
  So, because current Ruby version is = 3.2.11,
    version solving has failed.