feat: use setFailed instead of logError

[oleg-koval]

This Pull Request fulfills the following requirements:

• The commit message follows our guidelines.
• Tests for the changes have been added if needed.
• Does not affect documentation or it has been added or updated.

[coveralls]

Pull Request Test Coverage Report for Build 162108786

• 6 of 9 (66.67%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.08%) to 94.634%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/eventHandlers/checkSuite/index.ts	2	3	66.67%
src/eventHandlers/pullRequest/index.ts	2	3	66.67%
src/eventHandlers/push/index.ts	2	3	66.67%

Totals
Change from base Build 160043487:	0.08%
Covered Lines:	128
Relevant Lines:	135

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💛 - Coveralls

[viestat]

If I understand correctly this will make the check fail if the request to GitHub API fails.
This makes sense to me as it provides visibility of why the PR was not merged.

[merlinnot]

@oleg-koval Will it make it fail when the branch is out of date? That happens regularly, Dependabot has to rebase all PRs that are not up to date with the base branch.