[Doc]: Update-AzGallery -Tenant has incorrect documentation

### Type of issue

Code doesn't work

### Feedback

https://learn.microsoft.com/en-us/powershell/module/az.compute/update-azgallery?view=azps-15.4.0

this example shows

Update-AzGallery -ResourceGroupName $rgname -Name $galleryName -Permission Groups -Share -Tenant xxxxxxxx-xxx-xxxxxxx,zzzzzz-zzzzzzz-zzzzzz

that tenantIds should be comma separated values, but it doesn't work like it shows

I have got it to work by passing a string[]

for example
```powerShell
$tenantIds = @( 'xxxxxxxx-xxx-xxxxxxx'; 'zzzzzz-zzzzzzz-zzzzzz')
Update-AzGallery -ResourceGroupName $rgname -Name $galleryName -Permission Groups -Share -Tenant $tenantIds
```
works, but

```powerShell
$tenantIds = @( 'xxxxxxxx-xxx-xxxxxxx'; 'zzzzzz-zzzzzzz-zzzzzz')
Update-AzGallery -ResourceGroupName $rgname -Name $galleryName -Permission Groups -Share -Tenant $($tenantIds -join ',')
```
doesn't work

### Page URL

https://learn.microsoft.com/en-us/powershell/module/az.compute/update-azgallery?view=azps-15.4.0

### Content source URL

_No response_

### Author

_No response_

### Document Id

_No response_

### Platform Id

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