Pass Circle CI branch information to Coveralls (#22489)

Summary:
Trivial. Coveralls expects CI_BRANCH to be set. Circle uses CIRCLE_BRANCH instead. Without this, Coverals will attribute coverage reports to a "patch-1" branch.
Pull Request resolved: #22489

Differential Revision: D13306787

Pulled By: hramos

fbshipit-source-id: 70ad525168f249f4ca7f0370ba941632c33da8c5

Author: hramos

.circleci/config.yml

@@ -636,6 +636,11 @@ jobs:
   # Test Coverage
   js_coverage:
     <<: *js_defaults
+    environment:
+      - CI_BRANCH: $CIRCLE_BRANCH
+      - CI_PULL_REQUEST: $CIRCLE_PULL_REQUEST
+      - CI_BUILD_NUMBER: $CIRCLE_BUILD_NUM
+      - CI_BUILD_URL: $CIRCLE_BUILD_URL
     steps:
       - checkout
       - restore-cache: *restore-yarn-cache