Add unit tests in the scope of move to pdfkit package #5797

Job	Run time
get-content-file	3s
code-quality / npm run format	1m 12s
code-quality / npm run lint	3m 8s
code-quality / npm run typecheck	1m 18s
code-quality / npm run test:coverage	4m 31s
verify-local-e2e / e2e-tests (1)	2m 21s
verify-local-e2e / e2e-tests (2)	2m 2s
verify-local-e2e / e2e-tests (3)	2m 19s
verify-local-e2e / e2e-tests (4)	2m 58s
verify-local-e2e / merge-reports	0s
build-push-app-image	0s
deploy-staging	0s
deploy-preview	0s
verify-preview-e2e	0s
deploy-production	0s
test-production-text	0s
Send failure message to Slack	0s
	19m 52s

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