By Hannah Lang WASHINGTON (Reuters) – The dollar touched a one-week high against the yen on Wednesday, boosted by a jump in Treasury yields and investor expectations for a rebound in Chinese growth as COVID-19 curbs loosen. The dollar rallied by as much as 0.67% against the yen to 134.40 in Asian trading, the most since Dec. 20, when the Bank of Japan sent the pair spiraling lower with an unexpected loosening of the 10-year Japanese government bond yield policy band. That day, the yen staged its biggest one-day rally against the dollar in 24 years, closing 3.8% higher, as traders speculated ab…