Add chunk-friendly code path to encode_cf_datetime and encode_cf_timedelta
#10877
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| 10s | |
| 3s | |
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| 7m 50s | |
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| 3m 55s | |
| 7m 48s | |
| 7m 47s | |
| 7m 46s | |
| 1h 14m 6s |