Profile from skaffold env is not overwritten by profile command line switch

### Expected behavior
When a Profile is specified through the SKAFFOLD_PROFILE variable inside skaffold.env then it should get overwritten when skaffold is called with the -p switch on the command line.

### Actual behavior
The profile specified in the skaffold.env file is not overwritten by the command line argument. The profile in the skaffold.env file will also get used.

### Information

- Skaffold version: v2.2.0
- Operating system: Windows 10 using rancher-desktop and dockerd
- Installed via: skaffold.dev

### Steps to reproduce the behavior
When I use a skaffold.env file and set the profile to use like this:
```
SKAFFOLD_PROFILE=all
```
Then it always uses this profile. Also when I try to overwrite this setting by starting skaffold with `skaffold dev -p someProfile`.
I think this is due to the additive behaviour of the profiles argument. But in this case it is not that useful.