Change default pollInterval to 10m

[bobh66]

Description of your changes

Updated the default pollInterval to 10 minutes. Given the amount of time it takes to run terraform init/plan/apply the default 1m poll interval was likely to expire before the first reconciliation completed.

Users are free to adjust this value using ControllerConfig:

spec:
  args:
  - --poll=10m

I have:

• [X] Run make reviewable to ensure this PR is ready for review.

How has this code been tested

Applied to changes in a test cluster and verified that reconciliations are requeued with a 10 minute interval by default.

[bobh66]

I added documentation of the change and also information on performance tuning for the provider