Frozen string errors are emitted when using ruby 3.4

[hlascelles]

Ruby 3.4 emits Warnings for this gem as it modifies strings, which may be frozen in the future.

This line:

htmlcompressor/lib/htmlcompressor/rack.rb

Line 42 in 4c88494

content << part

More info: https://www.prateekcodes.dev/ruby-34-frozen-string-literals-rails-upgrade-guide/

Hope that makes sense!