Specifying a tarPath will push the image as well

[larsgroeber]

Fixes #1544

Description

The README specifies that adding --tarPath will create a tarball but also push the image to the registry.

In my opinion this behaviour would be expected since the --no-push option exists.

I updated the push.go file so that it will only check for errors returned by the tarball generation instead of returning from there.

Unfortunately there is no unit test for the tarball generation (that I could find), and I did not feel comfortable enough with the code to add one myself.

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Reviewer Notes

• The code flow looks good.
• Unit tests and or integration tests added.

Release Notes

Describe any changes here so maintainer can include it in the release notes, or delete this block.

- updates the way the `--tarPath` option works, it now pushes the image as well

[stevehipwell]

Could we get this merged ASAP?

[ManuelLR]

hey, this has been merged but is there any plan to make a release?