Enable coveralls

Author: bridadan

azure-pipelines.yml

@@ -65,7 +65,7 @@ jobs:
                 displayName: 'Install mbed-os test dependencies'
             -
                 script: |
-                    pip install --user flake8
+                    pip install flake8
                     python -m flake8
                 condition: eq(variables['extraActions'], 'true')
                 displayName: 'Enforce code style'
@@ -99,6 +99,12 @@ jobs:
                 script: "python -m coverage run setup.py test"
                 displayName: "Test mbed-greentea"
                 workingDirectory: 'legacy/mbed-greentea'
+            -
+                script: |
+                    python -m coverage combine .coverage legacy/*/.coverage
+                    python -m coveralls
+                condition: eq(variables['extraActions'], 'true')
+                displayName: 'Send coverage to coveralls'
     -
         job: Build
         dependsOn: Test