Add helm values for Twistlock `ImagePullPolicy`

Currently imagePullPolicy is not set for the Twistlock deployment - https://repo1.dso.mil/platform-one/big-bang/apps/security-tools/twistlock/-/blob/main/chart/templates/console/deployment.yaml

We should add this value into the deployment and set it to a helm value (i.e. something like {{ .Values.console.image.imagePullPolicy }}) with a default of IfNotPresent and then document this default/override in the table here.

AC:

• Twistlock console deployment updated to allow for overriding the pull policy via helm values
• Ways to override the pull policy added/documented in the table here