in_kubernetes_events: refactor time check to use struct flb_time.

[pwhelan]

Summary

Fixes a build error when building in_kubernetes_events caused by code that was not properly refactored. This is basically a reaplication of #8845 to master.

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Testing
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Backporting

• Backport to latest stable release.

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Fluent Bit is licensed under Apache 2.0, by submitting this pull request I understand that this code will be released under the terms of that license.

[ryanohnemus]

FYI this is also updated in https://github.com/fluent/fluent-bit/pull/8351/files#diff-1a15ea37009c42dc8379f6cb3b917480c16dca48c111b7bbbca3af0ee016ebeaR297, if we can bring that change up to this same milestone, i don't think we'd need to merge this change.

[edsiper]

@ryanohnemus FYI: we are going to merge #8351 for 3.1