Add a "reference must be newer" validator for `ARIA_S1_GUNW`

[jtherrmann]

Jira: https://asfdaac.atlassian.net/browse/TOOL-3567

Note: The above link is accessible only to members of ASF.

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We should add a "reference must be newer" validator for ARIA_S1_GUNW. Note that the order is the reverse of our usual convention of "reference must be older". @asjohnston-asf had asked for this validator as part of the multi-burst validation work, but we didn't end up including it in that effort, so it's still outstanding.