Why this change?
By ensuring the reset happens in an `ensure` code block, we ensure that
the code will always be run even if code fails or an error is raised.
This helps to prevent leaking custom network condition states and
improves the stability of our system tests.
Why this change?
The comment consists of an output that was copied from RSpec's default
output. This has the potential to mess with systems that are parsing
RSpec's output to fetch the spec failures as those systems are usually
looking for the first occurence of `Failures:`
Failure message on CI
```
Failures:
1) Network Disconnected Doesn't show the offline indicator when the site setting isn't present
Failure/Error: expect(page).to have_css("html.message-bus-offline")
expected to find css "html.message-bus-offline" but there were no matches
[Screenshot Image]: /__w/discourse/discourse/tmp/capybara/failures_r_spec_example_groups_network_disconnected_doesn_t_show_the_offline_indicator_when_the_site_setting_isn_t_present_764.png
~~~~~~~ JS LOGS ~~~~~~~
http://localhost:31338/uploads/default/test_0/optimized/1X/_129430568242d1b7f853bb13ebea28b3f6af4e7_2_512x512.png - Failed to load resource: net::ERR_INTERNET_DISCONNECTED
http://localhost:31338/categories - Error while trying to use the following icon from the Manifest: http://localhost:31338/uploads/default/test_0/optimized/1X/_129430568242d1b7f853bb13ebea28b3f6af4e7_2_512x512.png (Download error or resource isn't a valid image)
~~~~~ END JS LOGS ~~~~~
# ./spec/system/network_disconnected_spec.rb:35:in `block (3 levels) in <main>'
# ./spec/system/network_disconnected_spec.rb:8:in `with_network_disconnected'
# ./spec/system/network_disconnected_spec.rb:34:in `block (2 levels) in <main>'
# ./spec/rails_helper.rb:380:in `block (3 levels) in <top (required)>'
# ./spec/rails_helper.rb:380:in `block (2 levels) in <top (required)>'
# ./spec/rails_helper.rb:372:in `block (3 levels) in <top (required)>'
# ./vendor/bundle/ruby/3.2.0/gems/timeout-0.3.2/lib/timeout.rb:189:in `block in timeout'
# ./vendor/bundle/ruby/3.2.0/gems/timeout-0.3.2/lib/timeout.rb:196:in `timeout'
# ./spec/rails_helper.rb:367:in `block (2 levels) in <top (required)>'
# ./spec/rails_helper.rb:356:in `block (2 levels) in <top (required)>'
# ./vendor/bundle/ruby/3.2.0/gems/webmock-3.18.1/lib/webmock/rspec.rb:37:in `block (2 levels) in <top (required)>'
```
