By Alexandra Alper and Daphne Psaledakis WASHINGTON (Reuters) – The U.S. government put investment and export restrictions on dozens of Chinese companies on Thursday, including top drone maker DJI, accusing them of complicity in the oppression of China’s Uyghur minority or helping the military, further ratcheting up tensions between the world’s top two economies. Blaming DJI and seven other tech firms for supporting “the biometric surveillance and tracking” of Uyghurs, the U.S. Treasury Department added them to a list of entities suspected of having Chinese military links, barring Americans fr…