Merge #7150

7150: Proper group skip message for bundle update r=deivid-rodriguez a=deivid-rodriguez

### What was the end-user problem that led to this PR?

The problem was that when `bundle update` skipped groups, it shows a message about "gems not being installed". The message could be better and say "gems not being updated" instead, since that's what the user was trying to do.

### What was your diagnosis of the problem?

My diagnosis was that helper method was reused by the update and the install commands, but its message was specific to install.

### What is your fix for the problem, implemented in this PR?

My fix is to pass a parameter to the method with the calling command, so that the message is customized properly.

### Why did you choose this fix out of the possible options?

I chose this fix because it's easy.


Co-authored-by: David Rodríguez <deivid.rodriguez@riseup.net>