Example with wrong parameter (typo) (#14743)

Error: Update-AzGalleryImageVersion: A parameter cannot be found that matches parameter name 'GalleryImageName'.
Solution: rename GalleryImageName to GalleryImageDefinitionName

Author: FullByte

src/Compute/Compute/help/Update-AzGalleryImageVersion.md

@@ -46,7 +46,7 @@ PS C:\> $region1 = @{Name='West US';ReplicaCount=1}
 PS C:\> $region2 = @{Name='East US';ReplicaCount=2}
 PS C:\> $region3 = @{Name='Central US'}
 PS C:\> $targetRegions = @($region1,$region2,$region3)
-PS C:\> Update-AzGalleryImageVersion -ResourceGroupName $rgname -GalleryName $galleryName -GalleryImageName $imageName -Name $versionName -ReplicaCount 2 -PublishingProfileEndOfLifeDate $endOfLifeDate -TargetRegion $targetRegions
+PS C:\> Update-AzGalleryImageVersion -ResourceGroupName $rgname -GalleryName $galleryName -GalleryImageDefinitionName $imageName -Name $versionName -ReplicaCount 2 -PublishingProfileEndOfLifeDate $endOfLifeDate -TargetRegion $targetRegions
 ```
 
 Update a gallery image version.