Fix opening shell as user 'stack'

The usage of sudo with su is not recommended. It results in incosnistent
environment variables. Instead use just sudo with appropriate arguments.
The argument '-u stack' specifies that the sudo will execute as user 'stack'.
The last argument '-i' will launch an interactive shell.

Closes-Bug: #1938148

Change-Id: I42387660480377cdf9a0b04f190e7e1f21fb354f
1 file changed