Enable the use of prpcUtils.sh in the installer image

[rbogendoerfer]

Is your feature request related to a problem? Please describe.
In the course of Pega upgrades it is often necessary to also update Pega frameworks and applications. This could be done through the prpcUtils, which are part of the installer image anyway (directory scripts/utils). It would be great, if the helm charts offered another upgrade mode, which allows the use of prpcUtils.

Describe the solution you'd like
I think the following solution would be really useful and relatively easy to implement:
Add a new upgradeType "prpcutils"
Add a new property prpcUtilsCommand, which allows to select the prpc functionality, e.g. "import".
Add a new property prpcUtilsArguments, which allows to configure the selected command, e.g. specify the import files "--import.archive.path /myvol/PegaCRM.jar"
Files required for an import can be passed through the custom volumes and volumeMounts, which are already supported by the installer subchart.

Describe alternatives you've considered
Of couse applications, frameworks, hotfixes, etc. can be installed through the UI or through another system with prpcUtils/prpcSvcUtils installed. However it would be great to reuse the installer container for this purpose.