Add missing space for kubelet args in Prepare-Node.ps1 (#5863)

There was no space before `--cert-dir`. As a result, the command-line
arg had no effect and kubelet could not start.

Fixes #5857

Signed-off-by: Antonin Bas <antonin.bas@broadcom.com>

hack/windows/Prepare-Node.ps1

@@ -123,7 +123,7 @@ if ($InstallKubeProxy) {
     $StartKubeletFileContent += [Environment]::NewLine + '& C:\k\Prepare-ServiceInterface.ps1 -InterfaceAlias "HNS Internal NIC"' + [Environment]::NewLine
 }
 
-$StartKubeletFileContent += [Environment]::NewLine + '$global:KubeletArgs += "--cert-dir=$env:SYSTEMDRIVE\var\lib\kubelet\pki --config=/var/lib/kubelet/config.yaml --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --hostname-override=$(hostname) --pod-infra-container-image=`"mcr.microsoft.com/oss/kubernetes/pause:1.4.1`" --enable-debugging-handlers --cgroups-per-qos=false --enforce-node-allocatable=`"`" --resolv-conf=`"`" --node-ip=$env:NODE_IP"'
+$StartKubeletFileContent += [Environment]::NewLine + '$global:KubeletArgs += " --cert-dir=$env:SYSTEMDRIVE\var\lib\kubelet\pki --config=/var/lib/kubelet/config.yaml --bootstrap-kubeconfig=/etc/kubernetes/bootstrap-kubelet.conf --kubeconfig=/etc/kubernetes/kubelet.conf --hostname-override=$(hostname) --pod-infra-container-image=`"mcr.microsoft.com/oss/kubernetes/pause:1.4.1`" --enable-debugging-handlers --cgroups-per-qos=false --enforce-node-allocatable=`"`" --resolv-conf=`"`" --node-ip=$env:NODE_IP"'
 
 $targetVersion = [version]"1.28.0"