Better to download installers to temp folder instead of current folder

Normally there should be `temp` environment variable which points to the `temp` folder of the current user. So it would be better if the installation script can be changed to use temp, like below:

`Invoke-WebRequest -Uri https://aka.ms/installazurecliwindows -OutFile "$env:temp\AzureCLI.msi"; Start-Process msiexec.exe -Wait -ArgumentList "/I $env:temp\AzureCLI.msi /quiet"; rm "$env:temp\AzureCLI.msi"`

Document Details
⚠ Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.

ID: 8246b90a-efb1-03ce-f642-d3eb2441fc30
Version Independent ID: 2fdd20ef-7bd3-57bc-7957-93f4bb5377ce
Content: Install the Azure CLI for Windows
Content Source: docs-ref-conceptual/install-azure-cli-windows.md
Product: azure
Technology: azure-cli
GitHub Login: @dbradish-microsoft
Microsoft Alias: dbradishDocument Details
⚠ Do not edit this section. It is required for docs.microsoft.com ➟ GitHub issue linking.

ID: 8246b90a-efb1-03ce-f642-d3eb2441fc30
Version Independent ID: 2fdd20ef-7bd3-57bc-7957-93f4bb5377ce
Content: Install the Azure CLI for Windows
Content Source: docs-ref-conceptual/install-azure-cli-windows.md
Product: azure
Technology: azure-cli
GitHub Login: @dbradish-microsoft
Microsoft Alias: dbradish

Copied from [#2603](https://github.com/MicrosoftDocs/azure-docs-cli/issues/2603)