Make image page compatible with shakapacker v7 #1025

Job	Run time
test	12s
test_generated_apps (defaults, ackama_rails_template.config.yml, --skip-javascript)	4m 29s
test_generated_apps (all, ci/configs/all.yml, --skip-javascript)	6m 25s
test_generated_apps (all-typescript, ci/configs/all-typescript.yml, --skip-javascript)	8m 55s
test_generated_apps (basic, ci/configs/basic.yml, --skip-javascript)	5m 2s
test_generated_apps (basic-typescript, ci/configs/basic-typescript.yml, --skip-javascript)	4m 50s
test_generated_apps (github_actions, ci/configs/github_actions.yml, --skip-javascript)	5m 5s
test_generated_apps (react, ci/configs/react.yml, --skip-javascript)	5m 51s
test_generated_apps (react-typescript, ci/configs/react-typescript.yml, --skip-javascript)	6m 12s
test_generated_apps (sidekiq, ci/configs/sidekiq.yml, --skip-javascript)	5m 21s
test_generated_apps (devise, ci/configs/devise.yml, --skip-javascript)	6m 11s
test_generated_apps (basic_with_skips, ci/configs/basic.yml, --skip-spring --skip-javascript)	4m 1s
test_generated_apps (bootstrap, ci/configs/bootstrap.yml, --skip-javascript)	4m 12s
test_generated_apps (bootstrap-typescript, ci/configs/bootstrap-typescript.yml, --skip-javascript)	4m 53s
test_generated_apps (capistrano, ci/configs/deploy_with_capistrano.yml, --skip-javascript)	4m 10s
test_generated_apps (ackama_ec2_capistrano, ci/configs/deploy_with_ackama_ec2_capistrano.yml, --s...	4m 25s
	1h 20m 14s

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