Remove `runtimeParameters` from `v1beta1` Run spec

[aidandunlop]

Context

In #612, we renamed run.spec.runtimeParameters to `run.spec.parameters. This was first done in #613, but had to be reverted in #669 as there was an issue with the conversion between versions, whereby the runtimeParameters are being dropped entirely by k8s, meaning conversion wasn't working as expected.

This was addressed and reapplied in #670, in which the runtimeParameter field was left in v1beta1 to ensure conversion would work while v1beta1 was not the storage version.

We should now remove the runtimeParameters field completely from v1beta1, to ensure that users cannot apply a v1beta1 resource with runtimeParameters without getting an immediate resource syntax error. Whilst also ensuring the upgrade path between prior versions and v1beta1 remain functional.

ACs

• runtimeParameters is not part of v1beta1's Run spec