Remove Linux Azure pipelines build for Linux (#4452)

This retains Windows build

azure-pipelines.yml

@@ -3,21 +3,6 @@ jobs:
 - job: azure_pipeline_tests
   steps:
 
-  # Run a minimal set of tests in normal Linux pipeline builds
-  - task: Gradle@2
-    condition: eq(variables['Agent.OS'], 'Linux')
-    displayName: Build & test (Linux - minimal core)
-    env:
-      AWS_ACCESS_KEY_ID: $(aws.accessKeyId)
-      AWS_SECRET_ACCESS_KEY: $(aws.secretAccessKey)
-    inputs:
-        gradleWrapperFile: 'gradlew'
-        jdkVersionOption: '1.11'
-        options: "--no-daemon --continue"
-        tasks: "clean testcontainers:test --tests GenericContainerRuleTest"
-        publishJUnitResults: true
-        testResultsFiles: '**/TEST-*.xml'
-
   # Run all core tests when running the Windows CI tests
   - task: Gradle@2
     condition: eq(variables['Agent.OS'], 'Windows_NT')