Update dpage/pgadmin4 Docker tag to v7

This MR contains the following updates:

Package	Type	Update	Change
dpage/pgadmin4	ironbank-docker	major	6.21 -> 7.0
dpage/pgadmin4		major	6.21 -> 7.0
dpage/pgadmin4	stage	major	6.21 -> 7.0

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