MC-4064_correction: Fix redirects in Upgrade Compatibility Tool section (#8621)

* Fixed linting issues appeared after last pull from master

* Fixed Redirects for Safe Upgrade Tool

Author: danidelcar

src/guides/v2.3/javascript-dev-guide/widgets/widget_gallery.md

@@ -587,7 +587,6 @@ This example shows a use case for a gallery widget on any page:
 
 ```html
 <div class="image-gallery"></div>
- 
 <script>
 require ([
     'jquery',

src/upgrade-compatibility-tool/developer.md

@@ -2,7 +2,7 @@
 group: software-update-guide
 title: Developer information
 ee_only: True
-redirect from:
+redirect_from:
   - /safe-upgrade-tool/developer.html
 functional_areas:
   - Upgrade

src/upgrade-compatibility-tool/install.md

@@ -2,7 +2,7 @@
 group: software-update-guide
 title: Install
 ee_only: True
-redirect from:
+redirect_from:
   - /safe-upgrade-tool/install.html
 functional_areas:
   - Upgrade

src/upgrade-compatibility-tool/introduction.md

@@ -2,7 +2,7 @@
 group: software-update-guide
 title: Introduction
 ee_only: True
-redirect from:
+redirect_from:
   - /safe-upgrade-tool/introduction.html
 functional_areas:
   - Upgrade

src/upgrade-compatibility-tool/prerequisites.md

@@ -2,7 +2,7 @@
 group: software-update-guide
 title: Prerequisites
 ee_only: True
-redirect from:
+redirect_from:
   - /safe-upgrade-tool/prerequisites.html
 functional_areas:
   - Upgrade

src/upgrade-compatibility-tool/run.md

@@ -2,7 +2,7 @@
 group: software-update-guide
 title: Run the tool
 ee_only: True
-redirect from:
+redirect_from:
   - /safe-upgrade-tool/run.html
 functional_areas:
   - Upgrade