Throw exception for store side failures in Import-AzDataLakeStoreItem, Export-AzDataLakeStoreitem

[rahuldutta90]

Description

This does not change behavior in the successful cases, For failures earlier it used to write to the screen about the failure, now it will throw exceptions.

Checklist

• I have read the Submitting Changes section of CONTRIBUTING.md
• The title of the PR is clear and informative
• The appropriate ChangeLog.md file(s) has been updated:
  • For any service, the ChangeLog.md file can be found at src/{{SERVICE}}/{{SERVICE}}/ChangeLog.md
  • A snippet outlining the change(s) made in the PR should be written under the ## Upcoming Release header -- no new version header should be added
• The PR does not introduce breaking changes
• If applicable, the changes made in the PR have proper test coverage
• For public API changes to cmdlets:
  • a cmdlet design review was approved for the changes in this repository (Microsoft internal only)
  • the markdown help files have been regenerated using the commands listed here

[isra-fel]

This is considered a breaking change, because user must update their scripts to catch the new exception.
Here's our recommendation:

1. add breaking change description to the two cmdlets, telling the user that they'll be changed
2. (optional) release preview that has the breaking change if necessary
3. Check in the breaking change during our special release (around May)

[rahuldutta90]

This is considered a breaking change, because user must update their scripts to catch the new exception.
Here's our recommendation:

1. add breaking change description to the two cmdlets, telling the user that they'll be changed
2. (optional) release preview that has the breaking change if necessary
3. Check in the breaking change during our special release (around May)

@isra-fel Agree. I have sent out a pr: #11404 What is the date i should put as per https://github.com/Azure/azure-powershell/blob/master/documentation/breaking-changes/breaking-changes-attribute-help.md#with-deprecatedbyversion-and-changeineffectbydate

[isra-fel]

Continuing our conversation in #11404
Closing the PR for now as it won't be merged until the breaking change release (starting April 14th)
Please feel free to reopen then.
Thanks