Simplify constant TimeSpan retrieval

[xtqqczze]

The JIT compiler can treat TimeSpan.FromMinutes(1) as a constant and optimize it at compile time. In contrast, TimeSpan.Parse involves runtime string parsing and cannot be constant-folded, which adds unnecessary overhead.

TimeSpan.Parse may behave differently depending on culture settings.

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[Clockwork-Muse]

TimeSpan.Parse may behave differently depending on culture settings.

This may be true, but the original version also only ran parameter validation/construction once.