Relax codecov threshold (#269)

Relax codecov threshold

The updated codecov integration will occasionally flag PRs as
failing due to decreases in code coverage. Investigating the logs
points to this being sporadic changes due to occasional failures
when uploading code coverage. To avoid false positives and a
stopgap solution, the threshold for code coverage is set to 0.5%
instead of the default 0%

[ committed by @ashao ]
[ reviewed by @ankona ]

codecov.yml

@@ -6,6 +6,16 @@ coverage:
   round: down
   range: "70...100"
 
+  status:
+    patch:
+      default:
+       # Account for some variability in codecov
+       threshold: 0.5% 
+    project:
+      default:
+       # Account for some variability in codecov
+       threshold: 0.5% 
+
 parsers:
   gcov:
     branch_detection:
@@ -19,4 +29,4 @@ comment:
   behavior: default # update comment if already exists, otherwise post new
   require_changes: no
   require_base: no
-  require_head: yes
+  require_head: yes