Update jaegertracing/all-in-one Docker tag to v1.21.0

This MR contains the following updates:

Package	Type	Update	Change
jaegertracing/all-in-one	ironbank-docker	minor	1.20.0 -> 1.21.0
jaegertracing/all-in-one		minor	1.20.0 -> 1.21.0
jaegertracing/all-in-one	stage	minor	1.20.0 -> 1.21.0

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