fix(iam-role): ignore managed_policy_arns in late init

[haarchri]

Description of your changes

description is here: #929 (comment)
skip managed_policy_arns for late init

Fixes #929

I have:

• Run make reviewable test to ensure this PR is ready for review.

How has this code been tested

Manual: #929 (comment)
Uptest: https://github.com/upbound/provider-aws/actions/runs/6611409372

[haarchri]

@turkenf @jeanduplessis please take a look. I believe we require a fix release to address this issue, as fluctuating role policies can cause problems in a production environment.

[turkenf]

/test-examples="examples/iam/role.yaml"

[turkenf]

Thank you @haarchri, LGTM.

[mbbush]

My main question is whether we should also skip late init on inline_policy

[turkenf]

My main question is whether we should also skip late init on inline_policy

In order not to block this PR, we can handle inline_policy in another PR if it causes problems.

[blakebarnett]

Thanks for the quick fix!