feat(openmetrics): introduce OpenMetrics exporter #36752

Job	Run time
changes	10s
integration-sqlite (federation_features, 8.4, main, master)	5m 41s
integration-sqlite (dav_features, 8.4, main, master)	11m 6s
integration-sqlite (filesdrop_features, 8.4, main, master)	2m 7s
integration-sqlite (capabilities_features, 8.4, main, master)	2m 24s
integration-sqlite (features, 8.4, main, master)	12m 57s
integration-sqlite (sharees_features, 8.4, main, master)	8m 41s
integration-sqlite (openldap_numerical_features, 8.4, main, master)	1m 56s
integration-sqlite (files_reminders, 8.4, main, master)	1m 34s
integration-sqlite (openldap_features, 8.4, main, master)	2m 13s
integration-sqlite (ldap_features, 8.4, main, master)	2m 36s
integration-sqlite (routing_features, 8.4, main, master)	2m 8s
integration-sqlite (comments_features, 8.4, main, master)	2m 39s
integration-sqlite (collaboration_features, 8.4, main, master)	4m 2s
integration-sqlite (--tags ~@large files_features, 8.4, main, master)	19m 10s
integration-sqlite (remoteapi_features, 8.4, main, master)	1m 59s
integration-sqlite (sharing_features, 8.4, main, master)	24m 7s
integration-sqlite (videoverification_features, 8.4, main, master)	6m 26s
integration-sqlite (theming_features, 8.4, main, master)	2m 36s
integration-sqlite (file_conversions, 8.4, main, master)	2m 26s
integration-sqlite (setup_features, 8.4, main, master)	1m 54s
integration-sqlite-summary	20s
	1h 59m 12s

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