Dependabot private repo support (#16458)

* Update topics for Dependabot private repo support

* Fix typo

* Undo VS Code's auto-numbering

* Fix broken anchor

* Update content/github/administering-a-repository/configuration-options-for-dependency-updates.md

Co-authored-by: James Fletcher <42464962+jf205@users.noreply.github.com>

* Update content/github/managing-security-vulnerabilities/troubleshooting-dependabot-errors.md

Co-authored-by: James Fletcher <42464962+jf205@users.noreply.github.com>

* Update content/github/setting-up-and-managing-organizations-and-teams/managing-security-and-analysis-settings-for-your-organization.md

Co-authored-by: James Fletcher <42464962+jf205@users.noreply.github.com>

* Updated to put supported package managers in table

Alex suggested moving this information about which package managers
are not supported (bundler, hex, pip) into the table on the About
topic, rather than as text in the note box. This changes does that,
adding a new row to the table for hex (as discussed with Alex).

* Remove redundant image

Review comment asked for the line about filtering repos to be removed.
With that line gone there's no point showing the s/shot of a
filtered list.

* Updates for revised UI

As per comments from @thepwagner

* Make changes requested by Maya

Co-authored-by: James Fletcher <42464962+jf205@users.noreply.github.com>
Co-authored-by: Shati Patel <42641846+shati-patel@users.noreply.github.com>

data/reusables/dependabot/private-dependencies-note.md

@@ -0,0 +1,3 @@
+When running version updates, {% data variables.product.prodname_dependabot %} must be able to resolve all dependencies from their source to verify that version updates have been successful. If your manifest or lock files contain any dependencies hosted in private {% data variables.product.prodname_dotcom %} repositories within your organization, {% data variables.product.prodname_dependabot %} must be able to access those repositories. Organization owners can configure this. For more information, see "[Managing security and analysis settings for your organization](/github/setting-up-and-managing-organizations-and-teams/managing-security-and-analysis-settings-for-your-organization#allowing-dependabot-to-access-private-repositories)."
+
+Currently, {% data variables.product.prodname_dependabot %} version updates doesn't support manifest or lock files that contain any dependencies hosted in private registries, or in private {% data variables.product.prodname_dotcom %} repositories that belong to a different organization than the dependent project. 

data/reusables/dependabot/supported-package-managers.md

@@ -1,20 +1,23 @@
-Package manager | Supports vendoring
---- | :---:
-Bundler: `bundler` | **X**
-Cargo: `cargo` |
-Composer: `composer` |
-Docker: `docker` |
-Elm: `elm` |
-git submodule: `gitsubmodule` |
-GitHub Actions: `github-actions` |
-Go modules: `gomod` | **X**
-Gradle: `gradle` |
-Maven: `maven` |
-Mix: `mix` |
-npm: `npm` |
-NuGet: `nuget` |
-pip: `pip` |
-Terraform: `terraform` |
+The following table shows, for each package manager, whether {% data variables.product.prodname_dependabot %} supports: dependencies in private {% data variables.product.prodname_dotcom %} repositories, and vendored dependencies.
+
+Package manager | Private {% data variables.product.prodname_dotcom %} repositories | Vendoring 
+--- | :---:| :---:
+Bundler: `bundler` | | **✓** |
+Cargo: `cargo` | **✓** | |
+Composer: `composer` | **✓** | |
+Docker: `docker` | **✓** | |
+Elixir: `hex` | | |
+Elm: `elm` | **✓** | |
+git submodule: `gitsubmodule` | **✓** | |
+GitHub Actions: `github-actions` | **✓** | |
+Go modules: `gomod` | **✓** | **✓** |
+Gradle: `gradle` | **✓** | |
+Maven: `maven` | **✓** | |
+Mix: `mix` | **✓** | |
+npm: `npm` | **✓** | |
+NuGet: `nuget` | **✓** | |
+pip: `pip` | | |
+Terraform: `terraform` | **✓** | |
 
 {% note %}