[libvirt] Remove use of exec

Using the combination of `exec` and `systemd-run` is not compatable with containerd v1.6.6.

Change-Id: I80e3b92915830f7d2377688c9b229631348d4354

libvirt/Chart.yaml

@@ -15,7 +15,7 @@ apiVersion: v1
 appVersion: v1.0.0
 description: OpenStack-Helm libvirt
 name: libvirt
-version: 0.1.13
+version: 0.1.14
 home: https://libvirt.org
 sources:
   - https://libvirt.org/git/?p=libvirt.git;a=summary

libvirt/templates/bin/_libvirt.sh.tpl

@@ -179,4 +179,4 @@ EOF
 fi
 
 #NOTE(portdirect): run libvirtd as a transient unit on the host with the osh-libvirt cgroups applied.
-exec cgexec -g ${CGROUPS%,}:/osh-libvirt systemd-run --scope --slice=system libvirtd --listen
+cgexec -g ${CGROUPS%,}:/osh-libvirt systemd-run --scope --slice=system libvirtd --listen

releasenotes/notes/libvirt.yaml

@@ -14,4 +14,5 @@ libvirt:
   - 0.1.11 Remove unused overrides and update default image
   - 0.1.12 Add libvirt exporter as a sidecar
   - 0.1.13 Added OCI registry authentication
+  - 0.1.14 Remove use of exec in libvirt.sh
 ...