Update argoproj/argoexec Docker tag to v2.12.13

This MR contains the following updates:

Package	Type	Update	Change
argoproj/argoexec		minor	v2.1.1 -> v2.12.13
argoproj/argoexec	ironbank-docker	minor	v2.1.1 -> v2.12.13
argoproj/argoexec	stage	minor	v2.1.1 -> v2.12.13

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