🌱 Make make remove-spaces compatible with GNU and MAC OS X system

[damsien]

Why this PR does exist

This PR is motivated by this issue: #4327.

It is a fix about the make remove-spaces command that was only working on OS X and not GNU based system. It is because the behavior of the sed -i command is different between these two systems (see this stack exchange discussion).

• On OS X: sed -i ''
• On GNU: sed -i

So I added a check by using uname to use the sed -i in the correct way depending if we are on GNU based system or on OS X based system.

This PR follows this one #4330 that was not working. So it got reverted here #4331. This PR should works correctly. I cannot test on a MAC since I only have a linux system.

This PR needs to be tested by someone that has a MAC before merging.

Quick explanation

The bash -c is used because make cannot interpret if & else since it executes each line of the recipe in a separate shell (each command runs in isolation, making the condition ineffective).

Then we check only for "Linux" system and not "Darwin". Why? Because we want the default behavior of the command to be the same as previously (the command that worked for the "Darwin" system).
Thus, if it is a GNU system (uname = Linux), then we execute the modified command. Else, we execute the default behavior -> the previous command.

[k8s-ci-robot]

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[k8s-ci-robot]

Hi @damsien. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[damsien]

@camilamacedo86 Can you please test this one on your system? 😄