Let's consider a multiclassed Tempest Cleric with some levels in Storm Sorcerer (from Sword Coast Adventurer's Guide). That character also has the War Caster feat, which states
When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature.
Storm Sorcerer gives the character access to Gust, which can induce the following effect:
One Medium or smaller creature that you choose must succeed on a Strength saving throw or be pushed up to 5 feet away from you.
After using their Action to cast Gust on their turn and pushing a hostile creature 5 ft away, can this character use their Reaction to cast a cantrip such as Shocking Grasp or a suitable spell that targets a single creature, as stated by the War Caster feat?
Asked more generally: can I use movement induced by myself to trigger an Opportunity Attack?