[Bug Fix] azurerm_virtual_network_gateway_connection - Change shared_key to optional

[xuzhang3]

shared_key is not supported when the connection to ExpressRoute gateway so it should be optional. The test case did not run because the resource is related to ExpressRoute.

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Description

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Change Log

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• azurerm_resource - support for the thing1 property [GH-00000]

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 #27217

Note

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[stephybun]

This was previously Computed as well so that should be added back here as well.

Suggested change

	Optional: true,
	Optional: true,
	Computed: true,

[xuzhang3]

Closing this PR as the issue has been fixed by PR #27560

[github-actions]

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