Add --dry-run option to the generic create command

[kwiatekus]

Description

Allow users to generate yaml file instead of creating it on the cluster

For example via:

kyma alpha function create foo --dry-run -o yaml > function.yaml

AC

• the "dry-run" option should be applicable to all commands that use the generic "create" command
• dry-run w/o -oyaml flag should output the same as kubectl

k create ns boo --dry-run
namespace/boo created (dry run)

Reasons

We need to support generating function CR as yaml manifest so that users could have one approach to applying their application resources in a unified way for all CRs( using helm, kubect, kustomize or gitops approach)