Missing "terminal length 0" in sonic-cli shell.

[nagarwal03]

"terminal length" command is needed to specify page/output length of current terminal session. And in case of avoiding prompt "--more--" for long output, the value length of "0" should be allow to disable paging.

Current workaround is using " | no more " option, which is not normal practice for testing.

[nagarwal03]

Affected scripts: /tests/dell/ut/cli/interfaces/test_interface.py. I will update the script after this issue is fixed.