Make tests pass on single-digit days of month

[pbackus]

Previously, a regex used to match the result of DATE would fail on
the 1st through 9th of a month, because it expected one space between
the month and day instead of two.

[dlang-bot]

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Testing this PR locally

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[MoonlightSentinel]

You beat me to it

[pbackus]

Tried to re-run the tests but it seems like DAutoTest is not having a good day.