Added the policies to AccessApplication

[mabels]

The AccessApplication API's allow to retrieve and set the attached policies but in the type-struct the policies attribute is missing.

Description

Added the missing policies attribute to the struct.

Has your change been tested?

yes --- it works for me.

Screenshots (if appropriate):

Types of changes

What sort of change does your code introduce/modify?

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• This change is using publicly documented in cloudflare/api-schemas
  and relies on stable APIs.

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