Add CI_PROVIDER env variable to test tasks

script/vsts/linux.yml

@@ -34,6 +34,7 @@ phases:
       script/test
     env:
       CI: true
+      CI_PROVIDER: VSTS
     displayName: Run tests
 
   # This step is necessary in the short term due to a bug in the *NIX

script/vsts/macos.yml

@@ -31,6 +31,7 @@ phases:
       caffeinate -s script/test # Run with caffeinate to prevent screen saver
     env:
       CI: true
+      CI_PROVIDER: VSTS
     displayName: Run tests
 
   # This step is necessary in the short term due to a bug in the *NIX

script/vsts/windows.yml

@@ -36,6 +36,7 @@ phases:
   - script: script\test.cmd
     env:
       CI: true
+      CI_PROVIDER: VSTS
     displayName: Run tests
 
   - task: CopyFiles@2