CI: move coverage

closes pandas-dev#18895

Author: jreback

.travis.yml

@@ -52,10 +52,10 @@ matrix:
     # In allow_failures
     - dist: trusty
       env:
-        - JOB="3.5_CONDA_BUILD_TEST" TEST_ARGS="--skip-slow --skip-network" CONDA_BUILD_TEST=true COVERAGE=true
+        - JOB="3.5_CONDA_BUILD_TEST" TEST_ARGS="--skip-slow --skip-network" CONDA_BUILD_TEST=true
     - dist: trusty
       env:
-        - JOB="3.6" TEST_ARGS="--skip-slow --skip-network" PANDAS_TESTING_MODE="deprecate" CONDA_FORGE=true
+        - JOB="3.6" TEST_ARGS="--skip-slow --skip-network" PANDAS_TESTING_MODE="deprecate" CONDA_FORGE=true COVERAGE=true
     # In allow_failures
     - dist: trusty
       env:
@@ -80,7 +80,7 @@ matrix:
       # TODO(jreback)
       - dist: trusty
         env:
-          - JOB="3.5_CONDA_BUILD_TEST" TEST_ARGS="--skip-slow --skip-network" CONDA_BUILD_TEST=true COVERAGE=true
+          - JOB="3.5_CONDA_BUILD_TEST" TEST_ARGS="--skip-slow --skip-network" CONDA_BUILD_TEST=true
       - dist: trusty
         env:
           - JOB="2.7_SLOW" SLOW=true