Make analyzer test package name comparison case insensitive

Depending on whether we're using preview versions, some of the packages
may be downloaded by NuGet and have lowercased names, while at other
times they may be shipped in the packs folder and have mixed case.

Author: dsplaisted

src/Tests/Microsoft.NET.Build.Tests/GivenThatWeWantToUseAnalyzers.cs

@@ -64,8 +64,8 @@ public void It_resolves_analyzers_correctly(string language, string testAssetNam
                 case "C#":
                     analyzers.Select(x => GetPackageAndPath(x)).Should().BeEquivalentTo(new[]
                             {
-                                ("Microsoft.NET.Sdk", (string) null, "analyzers/Microsoft.CodeAnalysis.CSharp.NetAnalyzers.dll"),
-                                ("Microsoft.NET.Sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.NetAnalyzers.dll"),
+                                ("microsoft.net.sdk", (string) null, "analyzers/Microsoft.CodeAnalysis.CSharp.NetAnalyzers.dll"),
+                                ("microsoft.net.sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.NetAnalyzers.dll"),
                                 ("microsoft.netcore.app.ref", (string)null, "analyzers/dotnet/cs/System.Text.Json.SourceGeneration.dll"),
                                 ("microsoft.netcore.app.ref", (string)null, "analyzers/dotnet/cs/System.Text.RegularExpressions.Generator.dll"),
                                 ("microsoft.codequality.analyzers", "2.6.0", "analyzers/dotnet/cs/Microsoft.CodeQuality.Analyzers.dll"),
@@ -81,8 +81,8 @@ public void It_resolves_analyzers_correctly(string language, string testAssetNam
                 case "VB":
                     analyzers.Select(x => GetPackageAndPath(x)).Should().BeEquivalentTo( new[]
                         {
-                            ("Microsoft.NET.Sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.VisualBasic.NetAnalyzers.dll"),
-                            ("Microsoft.NET.Sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.NetAnalyzers.dll"),
+                            ("microsoft.net.sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.VisualBasic.NetAnalyzers.dll"),
+                            ("microsoft.net.sdk", (string)null, "analyzers/Microsoft.CodeAnalysis.NetAnalyzers.dll"),
                             ("microsoft.codequality.analyzers", "2.6.0", "analyzers/dotnet/vb/Microsoft.CodeQuality.Analyzers.dll"),
                             ("microsoft.codequality.analyzers", "2.6.0", "analyzers/dotnet/vb/Microsoft.CodeQuality.VisualBasic.Analyzers.dll"),
                             ("microsoft.dependencyvalidation.analyzers", "0.9.0", "analyzers/dotnet/Microsoft.DependencyValidation.Analyzers.dll")
@@ -161,7 +161,7 @@ public void It_resolves_multitargeted_analyzers()
                 var components = path.Split(new char[] { '/' }, 2);
                 string sdkName = components[0];
                 string pathInSdk = components[1];
-                return (sdkName, null, pathInSdk);
+                return (sdkName.ToLowerInvariant(), null, pathInSdk);
             }
 
             foreach (var nugetRoot in nugetRoots)
@@ -175,11 +175,11 @@ public void It_resolves_multitargeted_analyzers()
                     var packageVersion = components[1];
                     var pathInPackage = components[2];
                     //  Don't check package version for analyzers included in targeting pack, as the version changes during development
-                    if (packageName.Equals("microsoft.netcore.app.ref", StringComparison.Ordinal))
+                    if (packageName.Equals("microsoft.netcore.app.ref", StringComparison.OrdinalIgnoreCase))
                     {
                         packageVersion = null;
                     }
-                    return (packageName, packageVersion, pathInPackage);
+                    return (packageName.ToLowerInvariant(), packageVersion, pathInPackage);
                 }
             }