Optimize capybara selector to not wait

What does this MR do and why?

We already wait in the previous have_content step. So it is waste of time to wait 30 seconds to confirm 0 items.

Instead we immediately find all selectors on this step.

Screenshots or screen recordings

Before:

(arm64) tkgl2:gitlab tkuah$ bundle exec rspec /Users/tkuah/code/gdk-ee/gitlab/./spec/features/projects/branches_spec.rb:162
warning: parser/current is loading parser/ruby27, which recognizes2.7.6-compliant syntax, but you are running 2.7.5.
Please see https://github.com/whitequark/parser#compatibility-with-ruby-mri.
Run options: include {:focus=>true, :locations=>{"./spec/features/projects/branches_spec.rb"=>[162]}}

Test environment set up in 7.112807 seconds
Starting the Capybara driver server...
Capybara starting Puma...
* Version 5.6.5 , codename: Birdie's Version
* Min threads: 0, max threads: 4
* Listening on unix:///var/folders/gr/1dm_jlrd4g9_724jr3dmrrtm0000gn/T/20220922-87166-zbfjnv
.

Finished in 1 minute 0.9 seconds (files took 9.65 seconds to load)
1 example, 0 failures

After:

$ bundle exec rspec /Users/tkuah/code/gdk-ee/gitlab/./spec/features/projects/branches_spec.rb:162
warning: parser/current is loading parser/ruby27, which recognizes2.7.6-compliant syntax, but you are running 2.7.5.
Please see https://github.com/whitequark/parser#compatibility-with-ruby-mri.
Run options: include {:focus=>true, :locations=>{"./spec/features/projects/branches_spec.rb"=>[162]}}

Test environment set up in 7.127124 seconds
Starting the Capybara driver server...
Capybara starting Puma...
* Version 5.6.5 , codename: Birdie's Version
* Min threads: 0, max threads: 4
* Listening on unix:///var/folders/gr/1dm_jlrd4g9_724jr3dmrrtm0000gn/T/20220922-87474-1wjioqw
.

Finished in 31.71 seconds (files took 13.54 seconds to load)
1 example, 0 failures

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

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