Fix symbol publishing (#24879)
**Description:**
This pull request refactors the symbol publishing workflow that uses the
internal REST API. It addresses a breaking change introduced by the
`Az.Accounts` module update (v5.0.1+) where `Get-AzAccessToken` now
returns a `SecureString`. Additionally, it improves the structure and
robustness of the custom symbol publishing steps.
**Problem:**
1. The pipeline recently stopped working due to an update in the Azure
PowerShell `Az.Accounts` module. The `Get-AzAccessToken` cmdlet now
returns a `SecureString` by default, which was incompatible with the
previous script that expected a plain string token when setting a
pipeline variable.
2. The previous implementation used two separate tasks: one
`AzurePowerShell@5` task to generate the token and set it as a pipeline
variable, and a subsequent `pwsh` task to consume this variable and make
REST API calls. This separation required converting the `SecureString`
to plain text before setting the pipeline variable.
**Solution:**
To address these issues and improve the pipeline's design:
1. The "Generate an Azure Token" (`AzurePowerShell@5`) task and the
"Publish Symbols using internal REST API" (`pwsh`) task have been
**combined into a single `AzurePowerShell@5` task.**
2. Within this unified task:
* `Get-AzAccessToken` is called, and its `SecureString` output is stored
in a local PowerShell variable.
* The `SecureString` token is converted to plain text *only within the
scope of this script* and immediately before it's used in the
`Authorization` header for `Invoke-RestMethod` calls.
* The token is no longer passed between tasks via a pipeline variable,
enhancing security by limiting the scope of the plain text token.
**Key Changes:**
* **Enhanced `SecureString` Management:** The token remains a
`SecureString` for most of its lifetime within the script, reducing
exposure.
* **Improved Error Handling:** `try-catch` blocks have been added around
the token retrieval and `Invoke-RestMethod` calls for better error
reporting and pipeline stability.
* **Robust Parameter Handling:** Explicit conversion for boolean
parameters (e.g., `includePublicSymbolServer`) to ensure correct
PowerShell boolean types before JSON serialization.
