Use correct repo folder for linting addin documentation

tests/build.cake

@@ -17,17 +17,19 @@ var target = Argument("target", "Default");
 public class BuildData
 {
     public DirectoryPath RepoRootFolder { get; }
+    public DirectoryPath TestRootFolder { get; }
     public DirectoryPath SourceFolder { get; }
     public DirectoryPath DocsFolder { get; }
     public DirectoryPath OutputFolder { get; }
     public List<IIssue> Issues { get; }
 
     public BuildData(ICakeContext context)
     {
-        this.RepoRootFolder = context.MakeAbsolute(context.Directory("./"));
-        this.SourceFolder = this.RepoRootFolder.Combine("src");
-        this.DocsFolder = this.RepoRootFolder.Combine("docs");
-        this.OutputFolder = this.RepoRootFolder.Combine("output");
+        this.TestRootFolder = context.MakeAbsolute(context.Directory("./"));
+        this.RepoRootFolder = this.TestRootFolder.Combine("..");
+        this.SourceFolder = this.TestRootFolder.Combine("src");
+        this.DocsFolder = this.TestRootFolder.Combine("docs");
+        this.OutputFolder = this.TestRootFolder.Combine("output");
 
         this.Issues = new List<IIssue>();
     }

tests/build/analyze/markdownlint.cake

@@ -43,7 +43,7 @@ Task("Lint-AddinDocumentation")
 
     // Run markdownlint
     var settings =
-        MarkdownlintNodeJsRunnerSettings.ForDirectory(data.RepoRootFolder.Combine("../docs"));
+        MarkdownlintNodeJsRunnerSettings.ForDirectory(data.RepoRootFolder.Combine("docs"));
     settings.OutputFile = markdownLintLogFilePath;
     settings.ThrowOnIssue = false;
     RunMarkdownlintNodeJs(settings);