Update codecov settings (#1568)

Time spent on this PR: 0.1

## Pull request type

Please check the type of change your PR introduces:

- [ ] Bugfix
- [ ] Feature
- [ ] Code style update (formatting, renaming)
- [ ] Refactoring (no functional changes, no api changes)
- [x] Build related changes
- [ ] Documentation content changes
- [ ] Other (please describe):

## What is the current behavior?

Codecov almost always fails PRs.

## What is the new behavior?

This PR sets the coverage target to 0% and the threshold to 5%.

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Author: ClementWalter

codecov.yml

@@ -3,4 +3,8 @@ coverage:
     project:
       default:
         target: auto # auto compares coverage to the previous base commit
+        threshold: 5 # 5% threshold
+    patch:
+      default:
+        target: 0
   precision: 1