Update matomo Docker tag to v5.1.1

This MR contains the following updates:

Package	Type	Update	Change
matomo		patch	5.1.0 -> 5.1.1
matomo	ironbank-docker	patch	5.1.0-fpm -> 5.1.1-fpm
matomo	stage	patch	5.1.0-fpm -> 5.1.1-fpm

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