Don't install yarn in release step

Author: Tyriar

azure-pipelines.yml

@@ -71,10 +71,6 @@ jobs:
     inputs:
       versionSpec: '8.x'
     displayName: 'Install Node.js'
-  - task: geeklearningio.gl-vsts-tasks-yarn.yarn-installer-task.YarnInstaller@2
-    inputs:
-      versionSpec: "1.9.4"
-    displayName: 'Install Yarn'
   - script: |
       npm i
     displayName: 'Install dependencies and build'