feat(domains): update custom domains functionality

[zwhitfield3]

Description

Work Item
Work Item
Work Item

This PR updates and introduces a few new changes for custom domains and the Heroku CLI in general.

• Adds a pagination utility function that can be used to paginate any list request
• Adds keyValueParser utility function to parse any @oclif/core flags that may contain spaces such as ./bin/run domains -a testing-deploy --filter 'Domain Name=ztestdomain7'
• Warns users that the application they're attempting to display custom domains for contains over 100 domains
• Prompts users after aforementioned warning with a question on whether they would like to display the full list of custom domains

Testing

NOTE: In order to test these updates, you'll need an app with over 1,000 domains. If you don't have one, please ping me to add you to the test app, testing-deploy.

1. Pull down current branch
2. yarn it up
3. Check that the new warning and prompt functionality work via
   ./bin/run domains -a testing-deploy
4. Confirm the new warning and prompt appear like so:

›   Warning: This app has over 100 domains. Your terminal may not be configured to display the total
›   amount of domains. You can export all domains into a CSV file with: heroku domains -a example-app
›   --csv > example-file.csv
Display all 1003 domains? (Y/N)

5. Confirm that pressing enter auto selects no as the default option
6. Run the command again and type y. Confirm that all domains are shown.
7. Create a csv file by running the example command via
   ./bin/run domains -a testing-deploy --csv > test-domains-file.csv
8. Confirm all domains are outputted to the csv file
9. Apply a filter to the domains command via
   ./bin/run domains -a testing-deploy --filter 'Domain Name=ztestdomain7'
10. Confirm the prompt asks to display all 111 domains
11. Apply a filter to the domains command that will return less than 100 domains via
    ./bin/run domains -a testing-deploy --filter 'Domain Name=sara'
12. Confirm that no warning or prompt is displayed and that there is only 1 custom domain

[mattgraham]

👍 Workflow looks good;

we talked about fixing filtering --filter "blue.com" and having that list the results without the error message (assuming its under 100)

[justinwilaby]