Update .goreleaser.yml

Set v3 as latest tag in docker manifest

Author: LandonTClipp

.goreleaser.yml

@@ -71,6 +71,10 @@ docker_manifests:
     image_templates:
       - vektra/mockery:{{ .Tag }}-amd64
       - vektra/mockery:{{ .Tag }}-arm64
+  - name_template: vektra/mockery:latest
+    image_templates:
+      - vektra/mockery:{{ .Tag }}-amd64
+      - vektra/mockery:{{ .Tag }}-arm64
 
 release:
   prerelease: false