add short titles to frontmatter (#20131)

content/github/importing-your-projects-to-github/importing-source-code-to-github/adding-an-existing-project-to-github-using-the-command-line.md

@@ -9,6 +9,7 @@ versions:
   fpt: '*'
   ghes: '*'
   ghae: '*'
+shortTitle: Add a project locally
 ---
 {% data reusables.repositories.migrating-from-codeplex %}
 

content/github/importing-your-projects-to-github/importing-source-code-to-github/importing-a-git-repository-using-the-command-line.md

@@ -8,6 +8,7 @@ versions:
   fpt: '*'
   ghes: '*'
   ghae: '*'
+shortTitle: Import repo locally
 ---
 Before you start, make sure you know:
 

content/github/importing-your-projects-to-github/importing-source-code-to-github/importing-a-repository-with-github-importer.md

@@ -7,6 +7,7 @@ redirect_from:
   - /github/importing-your-projects-to-github/importing-a-repository-with-github-importer
 versions:
   fpt: '*'
+shortTitle: Use GitHub Importer
 ---
 {% tip %}
 

content/github/importing-your-projects-to-github/importing-source-code-to-github/index.md

@@ -18,5 +18,6 @@ children:
   - /importing-a-git-repository-using-the-command-line
   - /adding-an-existing-project-to-github-using-the-command-line
   - /source-code-migration-tools
+shortTitle: Import code to GitHub
 ---
 

content/github/importing-your-projects-to-github/importing-source-code-to-github/source-code-migration-tools.md

@@ -9,6 +9,7 @@ versions:
   fpt: '*'
   ghes: '*'
   ghae: '*'
+shortTitle: Code migration tools
 ---
 {% ifversion fpt %}
 

content/github/importing-your-projects-to-github/importing-source-code-to-github/updating-commit-author-attribution-with-github-importer.md

@@ -6,6 +6,7 @@ redirect_from:
   - /github/importing-your-projects-to-github/updating-commit-author-attribution-with-github-importer
 versions:
   fpt: '*'
+shortTitle: Update author GitHub Importer
 ---
 GitHub Importer looks for GitHub users whose email addresses match the authors of the commits in the repository you're importing. You can then connect a commit to its author using their email address or the author's GitHub username.