By Xinghui Kok and Claire Fu SINGAPORE, Dec 19 (Reuters) - A growing number of Chinese companies are looking to domicile in Singapore, betting a move to the trade-focused city-state would reduce risks their operations get disrupted by Sino-U.S. geopolitical tensions. The trend, billed as "Singapore washing" by some analysts, started gaining traction near the end of U.S. President Donald Trump's first ​presidency and has since accelerated, spreading to various sectors from critical minerals to tech and bi ...