By Natalia Zinets KYIV (Reuters) -The Ukrainian unit holed up beneath the Azovstal steelworks in Mariupol said on Monday its garrison was fulfilling orders to save the lives of troops, an apparent indication that the long siege there was coming to an end. The fighting at Azovstal in ruined Mariupol has symbolised Ukrainian resistance throughout Russia’s nearly three-month-old invasion. Most civilians who had sought shelter at the vast Soviet-era plant were evacuated earlier this month. “In order to save lives, the entire Mariupol garrison is implementing the approved decision of the Supreme Mi…