By Gul Yousafzai and Asif Shahzad QUETTA, Pakistan (Reuters) -Insurgents armed with bombs and guns attacked two Pakistani military bases overnight, killing seven soldiers while losing 13 of their own men, the army said on Thursday, in the latest violence in the resource-rich southwestern Balochistan province where China is investing. The attacks came hours before Pakistani Prime Minister Imran Khan arrived in Beijing for the opening of the Winter Olympics, where he will have meetings with Chinese President Xi Jinping and other leaders. “Our armed forces repulsed the big attacks,” Khan and Mini…