Error when executing `bundle exec jekyll serve`

[codedust]

Executing bundle exec jekyll serve results in an error (see below). However, bundle exec jekyll build works just fine.

$ bundle exec jekyll serve
jekyll 3.9.0 | Error:  no implicit conversion of Hash into Integer
./vendor/bundle/ruby/3.0.0/gems/pathutil-0.16.2/lib/pathutil.rb:502:in `read': no implicit conversion of Hash into Integer (TypeError)
	from ./vendor/bundle/ruby/3.0.0/gems/pathutil-0.16.2/lib/pathutil.rb:502:in `read'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/utils/platforms.rb:75:in `proc_version'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/utils/platforms.rb:40:in `bash_on_windows?'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/build.rb:77:in `watch'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/build.rb:43:in `process'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/serve.rb:93:in `block in start'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/serve.rb:93:in `each'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/serve.rb:93:in `start'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/lib/jekyll/commands/serve.rb:75:in `block (2 levels) in init_with_program'
	from ./vendor/bundle/ruby/3.0.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `block in execute'
	from ./vendor/bundle/ruby/3.0.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `each'
	from ./vendor/bundle/ruby/3.0.0/gems/mercenary-0.3.6/lib/mercenary/command.rb:220:in `execute'
	from ./vendor/bundle/ruby/3.0.0/gems/mercenary-0.3.6/lib/mercenary/program.rb:42:in `go'
	from ./vendor/bundle/ruby/3.0.0/gems/mercenary-0.3.6/lib/mercenary.rb:19:in `program'
	from ./vendor/bundle/ruby/3.0.0/gems/jekyll-3.9.0/exe/jekyll:15:in `<top (required)>'
	from ./vendor/bundle/ruby/3.0.0/bin/jekyll:23:in `load'
	from ./vendor/bundle/ruby/3.0.0/bin/jekyll:23:in `<top (required)>'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli/exec.rb:63:in `load'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli/exec.rb:63:in `kernel_load'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli/exec.rb:28:in `run'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli.rb:474:in `exec'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/vendor/thor/lib/thor/invocation.rb:127:in `invoke_command'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/vendor/thor/lib/thor.rb:392:in `dispatch'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli.rb:30:in `dispatch'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/vendor/thor/lib/thor/base.rb:485:in `start'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/cli.rb:24:in `start'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/exe/bundle:49:in `block in <top (required)>'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/lib/bundler/friendly_errors.rb:128:in `with_friendly_errors'
	from /usr/lib/ruby/gems/3.0.0/gems/bundler-2.2.21/exe/bundle:37:in `<top (required)>'
	from /usr/bin/bundle:23:in `load'
	from /usr/bin/bundle:23:in `<main>'