utils/github.rb: convert pr to integer

[iMichka]

Follow up adter #13124

I made the choice to convert the pr variable to an integer
at the very end and adjust the tests.

It would be maybe more consistent to work with an integer
everywhere, but this needs a more careful analysis and we
are in a hurry to fix the homberew-core upload CI

Fixes:
2022-04-11T20:19:34.1395885Z [31mError:[0m : Variable $pr of type Int! was provided invalid value
2022-04-11T20:19:34.1398279Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/utils/github/api.rb:261:in open_graphql' 2022-04-11T20:19:34.1399774Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/utils/github.rb:310:in get_workflow_run'
2022-04-11T20:19:34.1403699Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:418:in block (4 levels) in pr_pull' 2022-04-11T20:19:34.1405233Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:417:in each'
2022-04-11T20:19:34.1406723Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:417:in block (3 levels) in pr_pull' 2022-04-11T20:19:34.1408112Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.8/lib/ruby/2.6.0/fileutils.rb:128:in chdir'
2022-04-11T20:19:34.1408986Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.8/lib/ruby/2.6.0/fileutils.rb:128:in cd' 2022-04-11T20:19:34.1409813Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:400:in block (2 levels) in pr_pull'
2022-04-11T20:19:34.1410671Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/vendor/portable-ruby/2.6.8/lib/ruby/2.6.0/tmpdir.rb:93:in mktmpdir' 2022-04-11T20:19:34.1411495Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:399:in block in pr_pull'
2022-04-11T20:19:34.1412250Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:388:in each' 2022-04-11T20:19:34.1413056Z /home/linuxbrew/.linuxbrew/Homebrew/Library/Homebrew/dev-cmd/pr-pull.rb:388:in pr_pull'

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

---

[BrewTestBot]

Review period skipped due to critical label.

[Bo98]

Yeah I should add typechecking here at some point. I tested it via the way the tests did it but apparently pr-pull passes a string.

[iMichka]

Yeah the strings come from here

brew/Library/Homebrew/dev-cmd/pr-pull.rb

Lines 390 to 391 in d62558a

	url_match = arg.match HOMEBREW_PULL_OR_COMMIT_URL_REGEX
	_, user, repo, pr = *url_match

. Typechecking would have caught it. It was funny to see that the tests did not, as they were using an integer :)