/usr/lib/ruby/vendor_ruby/rspec/autorun.rb is in ruby-rspec-core 3.5.0c3e0m0s0-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | require 'rspec/core'
# Ensure the default config is loaded
RSpec::Core::Runner.autorun
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