Added stale-if-error and fixed bug for frontend cache staleWhileRevaidate config (#21886) #15036

Job	Run time
Setup	3m 16s
i18n	30s
Lint	47s
Admin tests - Chrome	0s
Database tests (Node 18.12.1, mysql8)	6m 14s
Browser tests	0s
Performance tests	0s
Regression tests (Node 20.11.1, mysql8)	2m 56s
Database tests (Node 20.11.1, mysql8)	6m 2s
Regression tests (Node 20.11.1, sqlite3)	1m 45s
Unit tests (Node 18.12.1)	1m 8s
Database tests (Node 20.11.1, sqlite3)	3m 23s
Unit tests (Node 20.11.1)	58s
Admin-X Settings tests	0s
Comments-UI tests	0s
Ghost-CLI tests	4m 3s
Signup-form tests	0s
Publish @tryghost/admin-x-activitypub	0s
All required tests passed or skipped	1s
Coverage	0s
Canary	0s
	31m 3s

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