resolve vsphere-syncer image from module config instead of 000-common

[xhable137]

Change how the vsphere-syncer sidecar image is resolved in helm_lib_csi_controller_manifests.
Previously the template resolved the image itself via helm_lib_module_common_image_no_fail
(pulling csiVsphereSyncer<Major><Minor> from 000-common digests).
Now the caller module passes the image explicitly via syncerImage in the config dict:

{{- $_ := set $csiControllerConfig "syncerImage" $syncerImage }}
The syncer container (and its VPA policy) only renders when both syncerEnabled: true
and syncerImage is non-empty. This decouples lib-helm from the image location
and allows vSphere modules to move the image out of 000-common.