Adds threshold to code coverage changes for project (#4040) (#4047)

* Fixes code coverage workflow failures for the project test due to inderect flakey changes

Signed-off-by: Ashwin P Chandran <ashwinpc@amazon.com>

* Adds changelog

Signed-off-by: Ashwin P Chandran <ashwinpc@amazon.com>

---------

Signed-off-by: Ashwin P Chandran <ashwinpc@amazon.com>
(cherry picked from commit 69b1854)
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

# Conflicts:
#	CHANGELOG.md

Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: Qingyang(Abby) Hu <abigailhu2000@gmail.com>

.github/.codecov.yml

@@ -1,7 +1,11 @@
 # https://docs.codecov.com/docs/codecov-yaml
+codecov:
+  require_ci_to_pass: yes
+
 coverage:
   status:
     project:
       default:
-        # https://docs.codecov.com/docs/commit-status#target
-        target: auto  # coverage must be equal or above the previous commit
+        target: auto
+        threshold: 2% # the leniency in hitting the target
+