Update the 95th percentile to 188cm or 6'2"

Why is this change being made?

This MR updates the height requirements for upgraded travel from 193.6cm or 6'4" to 188cm or 6'2". This is because:

1. The referenced Hermann Miller article defines a 95th percentile male as 6 feet, 2 inches (188 cm).
2. The reference to the Our World in Data article is a secondary source. I replaced this, using a primary source, the "Anthropometric Reference Data for Children and Adults: United States, 2015–2018" by the NATIONAL CENTER FOR HEALTH STATISTICS. This source is consistent with the Hermann Miller data.

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