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This is necessary because cloud-init on PVE resets keys at every reboot.

The shell executor is started in an healthy environment already;
the commands are needed mainly for the docker runner.

The runner is selected via a tag. No need to specify a customized port.

This reverts commit a0a8064d.
It is actually not necessary to use the base64 encoding anymore,
because the reason for which the variable was not passed to the
runner was the fact that the branch was not protected.

This is due to issue in difficulties in getting the right parms and keys to lektor

This was done to avoid running into [this
issue](https://github.com/vuejs/vue-cli/issues/3407)