Fix: Add missing 'fetch' parameter to in_schema.json and document it

The 'fetch' parameter has been implemented in the 'in' script since its
inception, allowing users to fetch additional branches during get
operations. However, it was missing from in_schema.json, causing the
schema validation to reject it as an unknown key.

Fixes #413.

Signed-off-by: Mathias Bogaert <[email protected]>

Author: analytically

README.md

@@ -402,6 +402,43 @@ correct key is provided set in `git_crypt_key`.
         the repository.
     </td>
   </tr>
+<tr>
+    <td><code>fetch</code><br/><i>Optional</i></td>
+    <td>
+        Additional branches to fetch and make available in the cloned repository.
+        This is useful when you need to perform operations like rebasing or
+        merging with branches other than the one being checked out.
+        <br/><br/>
+        Specify as a list of branch names. Each branch will be fetched from
+        origin and made available as a local branch.
+        <br/><br/>
+        <strong>Example:</strong> Fetching additional branches for rebasing
+        <pre>
+- get: source-code
+  params:
+    fetch:
+      - develop
+      - main
+      - feature/experimental
+        </pre>
+        After the <code>get</code> step completes, you can perform operations
+        like:
+        <pre>
+- task: rebase-on-main
+  config:
+    platform: linux
+    inputs:
+      - name: source-code
+    run:
+      path: sh
+      args:
+        - -exc
+        - |
+          cd source-code
+          git rebase main
+        </pre>
+    </td>
+  </tr>
   <tr>
     <td><code>fetch_tags</code><br/><i>Optional</i></td>
     <td>

assets/in_schema.json

@@ -1,5 +1,6 @@
 {
   "depth": "",
+  "fetch": "",
   "fetch_tags": "",
   "submodules": "",
   "submodule_recursive": "",