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Description

The server cannot be restarted when it's not in Ready state, this PR is add a state check before calling the Restart API.

Partially addresses #28298 fixed: #29219

PR Checklist

• I have followed the guidelines in our Contributing Documentation.
• I have checked to ensure there aren't other open Pull Requests for the same update/change.
• I have checked if my changes close any open issues. If so please include appropriate closing keywords below.
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  For example: “resource_name_here - description of change e.g. adding property new_property_name_here”

Changes to existing Resource / Data Source

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Testing

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Change Log

Below please provide what should go into the changelog (if anything) conforming to the Changelog Format documented here.

• azurerm_postgresql_flexible_server_configuration - check server status before restarting server [update postgresql flexible server failed of restarting error #29219]

This is a (please select all that apply):

• Bug Fix
• New Feature (ie adding a service, resource, or data source)
• Enhancement
• Breaking Change

Related Issue(s)

Fixes #29219