Refactor methods to reduce their Cognitive Complexity
Refactor methods to reduce their Cognitive Complexity

Refactored pkg/virt-controller/watch/migration.go.
Method refactored: "execute", "sync" and "findRunningMigrations".

Was detected by SonarCloud code scan as a code smell issue.

Signed-off-by: iholder <b6ebf050aad0538d1e30c557853a5c8924b66230@redhat.com>

kubevirt/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt,davidvossel/kubevirt,kubevirt/kubevirt,stu-gott/kubevirt,davidvossel/kubevirt,stu-gott/kubevirt,kubevirt/kubevirt,kubevirt/kubevirt