[BUG] Exit status is not 0 when the skunk score improved

**Branch/Commit:**

Version 0.5.2.

**Expected behavior:**

When comparing 2 branches, if the new branch has a better skunk score above the threshold, the exit status of the command should be 0 so it's not considered a failure.

**Actual behavior:**

When the score improves above the threshold, the exit status is non-zero so it's considered a failure in CI.

From this PR https://github.com/fastruby/skunk.fyi/actions/runs/6655872886/job/18087134376?pr=103


**Steps to reproduce:**

Run the compare command for a new PR improving the skunk score average by more than the threshold.

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