Hide secondary pages in Getting Started (#226)

* Hide secondary pages in Getting Started

* Update

* Optimised images with calibre/image-actions

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Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

Author: 4ian

docs/gdevelop5/behaviors/add-behavior-list.png

@@ -0,0 +1 @@
+hide: true

docs/gdevelop5/behaviors/add-behavior-properties-panel.png

@@ -19,7 +19,7 @@ The installer is based on *NSIS*, so you can find online resources to use it fro
 For usage in a company or university, we recommend installing it "system-wide" (i.e: for all users). Each user will have their own preferences.
 
 You can create a Powershell script:
-![](/gdevelop5/getting_started/batch-install-gdevelop-company-university/pasted/20220513-085548.png)
+![](./20220513-085548.png)
 
 Something like this (adapt the executable path):
 

docs/gdevelop5/behaviors/community-behaviors.png

@@ -0,0 +1 @@
+hide: true