tsv test pipeline (#26539)

* tsv test pipeline

* test failure

* Update eng/tools/TypeSpecValidation/test/git-diff.test.ts

* Update eng/pipelines/typespec-validation-ci.yml

Co-authored-by: Mike Harder <mharder@microsoft.com>

* Update eng/pipelines/typespec-validation-ci.yml

Co-authored-by: Mike Harder <mharder@microsoft.com>

---------

Co-authored-by: Mike Harder <mharder@microsoft.com>

Author: ckairen

eng/pipelines/typespec-validation-ci.yml

@@ -0,0 +1,40 @@
+trigger:
+  branches:
+    include:
+    - main
+    - typespec-next
+
+pr:
+  branches:
+    include:
+    - main
+    - typespec-next
+  paths:
+    include:
+    - package-lock.json
+    - package.json
+    - tsconfig.json
+    - eng/tools/TypeSpecValidation
+
+jobs:
+- job: Test_TypeSpec_Validation
+
+  strategy:
+    matrix:
+      Linux:
+        Pool: azsdk-pool-mms-ubuntu-2204-general
+        OsVmImage: ubuntu-22.04
+      Windows:
+        Pool: azsdk-pool-mms-win-2022-general
+        OsVmImage: windows-2022
+
+  pool:
+    name: $(Pool)
+    vmImage: $(OSVmImage)
+
+  steps:
+  - template: /eng/pipelines/templates/steps/npm-install.yml
+
+  - script: npm test
+    displayName: Test TypeSpecValidation Tool
+    workingDirectory: $(Build.SourcesDirectory)/eng/tools/TypeSpecValidation