Updates codecov configuration for the flag settings and notification interaction

.codecov.yml

@@ -1,3 +1,17 @@
+codecov:
+  require_ci_to_pass: true
+# https://docs.codecov.com/docs/flags#recommended-automatic-flag-management
+# Require each flag to have 1 upload before notification
+flag_management:
+  default_rules:
+    after_n_builds: 1
+  individual_flags:
+    - name: backend
+      paths:
+        - src/
+    - name: frontend
+      paths:
+        - src-ui/
 # https://docs.codecov.com/docs/pull-request-comments
 # codecov will only comment if coverage changes
 comment: