Update openpolicyagent/conftest Docker tag to v0.39.2

This MR contains the following updates:

Package	Type	Update	Change
openpolicyagent/conftest	ironbank-docker	patch	v0.39.1 -> v0.39.2
openpolicyagent/conftest		patch	v0.39.1 -> v0.39.2
openpolicyagent/conftest	stage	patch	v0.39.1 -> v0.39.2

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