fix max_retries and max_retry_wait_seconds provider settings

[displague]

Fix errors caused by incorrect provider configuration key names and values:

  Warning  CannotObserveExternalResource  55s (x25 over 107s)  managed/device.equinixmetal.jet.crossplane.io/v1alpha1, kind=device  cannot run refresh: refresh failed: Extraneous JSON object property: No argument or block type is named "max_retries_wait_seconds".: File name: main.tf.json
Incorrect attribute value type: Inappropriate value for attribute "max_retries": a number is required.: File name: main.tf.json

Description of your changes

Fixes #

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