PARIS, March 12 (Reuters) - French unions will keep on fighting against President Emmanuel Macron's pension reform plan despite the upper house of parliament approving the text on Saturday, a leader of one of the main unions said on Sunday. Laurent Berger, secretary general of France's largest union the CFDT, also warned Macron's government against forcing the parliament's hand by pushing the text through without a vote from MPs of the National Assembly, using a procedure known as 49:3 after the related article in the French constitution. See here for a complete list of exchanges and delays