Add search, install, uninstall gate tests

Author: Nigusu-Allehu

test/NuGet.Tests.Apex/NuGet.Tests.Apex/NuGetEndToEndTests/NuGetUITestCase.cs

@@ -23,6 +23,7 @@ public class NuGetUITestCase : SharedVisualStudioHostTestClass
 
         [TestMethod]
         [Timeout(DefaultTimeout)]
+        [TestCategory("Gate")]
         public async Task SearchPackageFromUI()
         {
             // Arrange
@@ -49,6 +50,7 @@ public async Task SearchPackageFromUI()
 
         [TestMethod]
         [Timeout(DefaultTimeout)]
+        [TestCategory("Gate")]
         public async Task InstallPackageFromUI()
         {
             // Arrange
@@ -107,6 +109,7 @@ public async Task InstallPackageToProjectsFromUI()
 
         [TestMethod]
         [Timeout(DefaultTimeout)]
+        [TestCategory("Gate")]
         public async Task UninstallPackageFromUI()
         {
             // Arrange
@@ -140,6 +143,7 @@ public async Task UninstallPackageFromUI()
 
         [TestMethod]
         [Timeout(DefaultTimeout)]
+        [TestCategory("Gate")]
         public async Task UpdatePackageFromUI()
         {
             // Arrange