Description of problem:
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Set an env var using odo config set --env.
2. Unset it using odo config unset --env foo=bar.
3. Unset it using odo config unset --env foo (don't mention the value of foo this time).
4. Verify output of odo config view at the end of each step
odo says that it has successfully unset the env var but it actually hasn't.
Either odo config unset should complain that it can't handle the input given by user or unset the value as user would expect
Fix via - https://github.com/openshift/odo/pull/2275