Specify correctly which repo is being cloned during install command

What does this merge request do and why?

When using the gdk install command with a custom gitlab_repo argument, the installation message displays:

"Cloning gitlab-org/gitlab”

This message appears regardless of which repository is actually being cloned.

Now when users specifies a custom repository (such as git@gitlab.com:gitlab-org/gitlab-foss.git) via the gitlab_repo argument, the message shows:

"Cloning git@gitlab.com:gitlab-org/gitlab-foss.git”

How to set up and validate locally

With gitlab_repo parameter

1. Install GDK

2. Run GDK installation with a custom repository, for example:

   gdk install gitlab_repo=https://gitlab.com/your-fork/gitlab.git

3. Observe the installation output in terminal should be

   Cloning https://gitlab.com/your-fork/gitlab.git

Without gitlab_repo parameter

1. Install GDK

2. Run GDK installation without custom repository:

   gdk install

3. Observe the installation output in terminal should be

   Cloning https://gitlab.com/gitlab-org/gitlab.git

Impacted categories

The following categories relate to this merge request:

• gdk-reliability - e.g. When a GDK action fails to complete.
• gdk-usability - e.g. Improvements or suggestions around how the GDK functions.
• gdk-performance - e.g. When a GDK action is slow or times out.

Merge request checklist

• This change is backward compatible. If not, please include steps to communicate to our users.
• Tests added for new functionality. If not, please raise an issue to follow-up.
• Documentation added/updated, if needed.
• Announcement added, if change is notable.
• gdk doctor test added, if needed.
• Add the ~highlight label if this MR should be included in the CHANGELOG.md.