Fix custom-docker-opts

[jc-sanchez]

docker.service fails to start because /dind/containerd does not exist.
Move the creation of the directory from wrapkubeadm to the Dockerfile
Fixes #266

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[jc-sanchez]

/check-cla

[jc-sanchez]

/assign @roberthbailey

[jc-sanchez]

/cc @ivan4th

[roberthbailey]

Re-assigning to project maintainers.

/assign @pigmej @ivan4th
/unassign @roberthbailey

[ivan4th]

Thanks for the PR!
/lgtm
/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ivan4th, jc-sanchez

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