[AIRFLOW-5680] Fixes Kubernetes hangs (apache#6347)

.travis.yml

@@ -31,26 +31,6 @@ stages:
   - test
 jobs:
   include:
-    - name: "Tests postgres python 3.6"
-      env: BACKEND=postgres ENV=docker
-      python: "3.6"
-      stage: test
-    - name: "Tests sqlite python 3.5"
-      env: BACKEND=sqlite ENV=docker
-      python: "3.5"
-      stage: test
-    - name: "Tests mysql python 3.7"
-      env: BACKEND=mysql ENV=docker
-      python: "3.7"
-      stage: test
-    - name: "Tests postgres kubernetes python 3.6 (persistent)"
-      env: BACKEND=postgres ENV=kubernetes KUBERNETES_VERSION=v1.15.0 KUBERNETES_MODE=persistent_mode
-      python: "3.6"
-      stage: test
-    - name: "Tests postgres kubernetes python 3.6 (git)"
-      env: BACKEND=postgres ENV=kubernetes KUBERNETES_VERSION=v1.15.0 KUBERNETES_MODE=git_mode
-      python: "3.6"
-      stage: test
     - name: "Static checks (no pylint, no licence check)"
       stage: pre-test
       script: ./scripts/ci/ci_run_all_static_tests_except_pylint_licence.sh
@@ -63,8 +43,28 @@ jobs:
     - name: "Build documentation"
       stage: pre-test
       script: ./scripts/ci/ci_docs.sh
+    - name: "Tests postgres kubernetes python 3.6 (persistent)"
+      env: BACKEND=postgres ENV=kubernetes KUBERNETES_VERSION=v1.15.0 KUBERNETES_MODE=persistent_mode
+      python: "3.6"
+      stage: test
+    - name: "Tests postgres kubernetes python 3.6 (git)"
+      env: BACKEND=postgres ENV=kubernetes KUBERNETES_VERSION=v1.15.0 KUBERNETES_MODE=git_mode
+      python: "3.6"
+      stage: test
+    - name: "Tests postgres python 3.6"
+      env: BACKEND=postgres ENV=docker
+      python: "3.6"
+      stage: test
+    - name: "Tests sqlite python 3.5"
+      env: BACKEND=sqlite ENV=docker
+      python: "3.5"
+      stage: test
+    - name: "Tests mysql python 3.7"
+      env: BACKEND=mysql ENV=docker
+      python: "3.7"
+      stage: test
 services:
   - docker
 before_install:
   - ./scripts/ci/ci_before_install.sh
-script: "./scripts/ci/ci_run_airflow_testing.sh"
+script: travis_wait 30 "./scripts/ci/ci_run_airflow_testing.sh"

airflow/kubernetes/k8s_model.py

@@ -15,7 +15,7 @@
 # specific language governing permissions and limitations
 # under the License.
 """
-Classes for interacting with Kubernetes API
+Classes for interacting with Kubernetes API.
 """
 
 from abc import ABC, abstractmethod