Add postUpgradeCommand for upgrading Alloy wrapper chart dependencies

Add postUpgradeCommand for upgrading Alloy wrapper chart dependencies, make sure it is whitelisted

Related to big-bang/product/packages/alloy#56

Test in a renovate dev cluster..

https://repo1.dso.mil/big-bang/pipeline-templates/renovate-runner/-/blob/main/dev/TESTING_DEVELOPMENT.md