Update quay.io/skupper/config-sync Docker tag to v1.5.3

This MR contains the following updates:

Package	Type	Update	Change
quay.io/skupper/config-sync		patch	1.5.2 -> 1.5.3
quay.io/skupper/config-sync	ironbank-docker	patch	1.5.2 -> 1.5.3
quay.io/skupper/config-sync	stage	patch	1.5.2 -> 1.5.3

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