api: set num_threads to 8 #3976

Job	Run time
api-check-needed	5s
Lint: ClientPrint (ESLint)	20s
e2e-check-needed	7s
frontend-check-needed	4s
Tests: PDF	20s
Lint: Print (ESLint)	27s
Tests: Print	48s
Lint: API (php-cs-fixer)	35s
Tests: API	4m 39s
Lint: Frontend (ESLint)	0s
Tests: Frontend	0s
Lint: e2e (ESLint)	23s
Tests: End-to-end build / Tests: End-to-end (build job)	1m 7s
Tests: End-to-end run / Tests: End-to-end (chrome)	4m 31s
Tests: End-to-end run / Tests: End-to-end (firefox)	5m 9s
Tests: End-to-end run / Tests: End-to-end (edge)	4m 48s
Finish coveralls report	0s
workflow-success	1s
Send out CI success event	0s
	23m 24s

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