Fix several DX and test errors

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This MR fixes a couple issues with the codebase that adds quality of life for developers (DX), and hopefully makes one of the flakey tests a little less flakey:

• Flakey test "destroy" functions that were previously named the same as functions in the "acceptance" tag are now renamed. This lets the default vscode settings run any accepts/flakey/settings test without needing to change tags.
• Read in the policyProjectId from the ID during the Read function in both project/group security policy attachment to prevent an issue where the policy project GraphQL ID was occasionally not populated.
• Fix an issue with the SecurityProjectUnassignResponse struct where the error format wasn't proper