[image-builder] Drop superfluous imports

Author: geropl

components/image-builder-mk3/go.mod

@@ -93,8 +93,6 @@ require (
 
 require (
 	github.com/Microsoft/hcsshim v0.11.4 // indirect
-	github.com/blang/semver v3.5.1+incompatible // indirect
-	github.com/configcat/go-sdk/v7 v7.6.0 // indirect
 	github.com/containerd/errdefs v0.1.0 // indirect
 	github.com/containerd/log v0.1.0 // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect