Update alpine Docker tag to v3.18.3

This MR contains the following updates:

Package	Type	Update	Change
alpine	ironbank-docker	patch	3.18.2 -> 3.18.3
alpine		patch	3.18.2 -> 3.18.3
alpine	final	patch	3.18.2 -> 3.18.3
alpine	stage	patch	3.18.2 -> 3.18.3

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