[INTW26] add endpoint for setting reviewerHasConflict to true

[chene0]

Notion ticket link

Implement Report Conflict Feature

Implementation description

• Add reportReviewConflict mutation resolver and service to set column reviewerHasConflict to true for a target row in table reviewed_applicant_records

Steps to test

1. Call mutation createReviewedApplicantRecord with some valid input applicantRecordId and reviewerId, confirm that column reviewerHasConflict for that applicantRecordId and reviewerId in table reviewed_applicant_records is false
2. Call mutation reportReviewConflict with the same input applicantRecordId and reviewerId, confirm that column reviewerHasConflict for the same row changed to true

What should reviewers focus on?

Checklist

• My PR name is descriptive and in imperative tense
• My commit messages are descriptive and in imperative tense. My commits are atomic and trivial commits are squashed or fixup'd into non-trivial commits
• I have run the appropriate linter(s)
• I have requested a review from the PL, as well as other devs who have background knowledge on this PR or who will be building on top of this PR

[SaqAsh]

LGTM, just fix some of the small nitpicks I had, and make sure that when you touch a file that you format the imports using alt shift/option o command so we have clean files :)

[mxc-maggiechen]

LGTM!