[Smoketest]Add try 3 times with 30s sleeping time

[lijinpei2008]

Description

Add try 3 times with 30s sleeping time between each try.

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)
    • {Please put the link here}
  • the markdown help files have been regenerated using the commands listed here

[isra-fel]

Have you tested it?

[lijinpei2008]

Have you tested it?

Yes, passed the test locally whether it's PowerShell or Windows Powershell.

[isra-fel]

How about the negative case: you deliberately make a test case fail and check:

1. if the error message contains meaningful info (like exception message and stack trace)
2. if the case is retried

[lijinpei2008]

How about the negative case: you deliberately make a test case fail and check:

1. if the error message contains meaningful info (like exception message and stack trace)
2. if the case is retried

Yes, change the value of the environment variable "$ErrorActionPreference" to "Continue" when the command runs incorrectly and retry.
If it succeeds, it skips. If the error continues, and the error message is printed on the screen. This behavior will continue 2 times.
For example, when I provide a wrong parameter, I can see an explicit error message telling me that the parameter "Names" does not exist.

[isra-fel]

LGTM