Add final newlines to files. (#7432)

More conventional and makes it nicer when doing things like running cat to quickly look at the file like I was doing when I noticed this.

.azure-pipelines/advanced.yml

@@ -15,4 +15,4 @@ schedules:
 
 jobs:
   - template: templates/tests-suite.yml
-  - template: templates/installer-tests.yml
+  - template: templates/installer-tests.yml

.azure-pipelines/main.yml

@@ -8,4 +8,4 @@ pr:
   - master
 
 jobs:
-  - template: templates/tests-suite.yml
+  - template: templates/tests-suite.yml

.azure-pipelines/templates/installer-tests.yml

@@ -28,4 +28,4 @@ jobs:
       - script: |
           set PATH=%ProgramFiles(x86)%\Certbot\bin;%PATH%
           venv\Scripts\python -m pytest certbot-ci\certbot_integration_tests\certbot_tests -n 4
-        displayName: Run integration tests
+        displayName: Run integration tests