Remove test pipeline

devops/pr-gate-os.yml

@@ -1,40 +0,0 @@
-name: $(Date:yyyyMMdd).$(Rev:r)
-
-variables:
-  - group: azureResourceKeys
-
-stages:
-  - stage: static_analysis
-    jobs:
-    - job: flake8_linux_py36
-      pool:
-        vmImage: 'ubuntu-latest'
-      steps:
-        - template: templates/base/run-linter.yml
-          parameters:
-            pyVersion: '3.6'
-
-  - stage: unit_tests
-    dependsOn: static_analysis
-    jobs:
-      - template: templates/run-tests-on-multiple-os-py.yml
-        parameters:
-          pyVersions: ['3.6']
-          testTypes: ['unit', 'io']
-          imageOSs: ['ubuntu-18.04']  # 'windows-latest', 'macos-latest'
-
-  - stage: e2e_tests
-    dependsOn: static_analysis
-    jobs:
-      - template: templates/run-tests-on-multiple-os-py.yml
-        parameters:
-          pyVersions: ['3.6']
-          testTypes: ['azure']
-          imageOSs: ['ubuntu-18.04']  # 'windows-latest', 'macos-latest'
-
-  - stage: collect_final_code_coverage
-    dependsOn: 
-      - unit_tests
-      - e2e_tests
-    jobs:
-      - template: templates/merge-cov-reports.yml