Support configuring script pod resource requirements

[APErebus]

A customer appears to be having resource contention with a large number of script pods. They would like to be able to modify the resource requirements of script pods.

This PR adds a new values node in the scriptPods section. These resources are then serialized to JSON and passed to the agent-tentacle container as an environment variable. This is consumed by the change in OctopusDeploy/OctopusTentacle#977

Tested locally with

--set scriptPods.resources.limits.cpu="150m" `
--set scriptPods.resources.limits.memory="250Mi" `
--set scriptPods.resources.requests.cpu="50m" `
--set scriptPods.resources.requests.memory="150Mi" 

resulted in tentacle env var

resulted in script pods config

[changeset-bot]

🦋 Changeset detected

Latest commit: b178a1e

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
kubernetes-agent	Minor

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[liam-mackie]

LGTM! Thanks for the 🍐 on the review.
For posterity - the test should pass once the tentacle PR is merged and the build is available on dockerhub.