Revert "[SwiftPM] Update 'firebaseVersion' to 10.19.1 (#12195)" #8213

Job	Run time
Check changed files	0s
binary_size_metrics (iOS)	7m 14s
pod-lib-lint-abtesting (iOS)	8m 48s
pod-lib-lint-auth (iOS)	10m 30s
pod-lib-lint-database (iOS)	11m 57s
pod-lib-lint-dynamiclinks (iOS)	21m 22s
pod-lib-lint-firestore (iOS)	45m 57s
pod-lib-lint-functions (iOS)	4m 57s
pod-lib-lint-inappmessaging (iOS)	9m 26s
pod-lib-lint-messaging (iOS)	12m 9s
pod-lib-lint-performance (iOS)	8m 46s
pod-lib-lint-remoteconfig (iOS)	10m 46s
pod-lib-lint-storage (iOS)	7m 9s
create_report	11m 35s
	2h 50m 36s

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