docs: videos in gif format (#321)

Signed-off-by: Philippe Martin <[email protected]>

Author: feloy

README.md

@@ -7,13 +7,13 @@ running on Podman, and start new services, with advanced options.
 
 The extension discovers existing PostgreSQL instances where configuration is set using environment variables.
 
-![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres1.mp4)
+![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres1.gif)
 
 ## Start a PgAdmin instance connected to an existing PostgreSQL instance
 
 From the Containers List page, you can start a PgAdmin instance connected to a discovered PostgreSQL instance.
 
-![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres2.mp4)
+![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres2.gif)
 
 ## Start a new PostgreSQL instance, with optional PgAdmin
 
@@ -22,10 +22,10 @@ optionally attach a PgAdmin instance to the PostgreSQL instance.
 
 If the PgAdmin option is chosen, two containers will be created in a Pod, one for the PostgreSQL instance and one for the PgAdmin instance.
 
-![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres3.mp4)
+![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres3.gif)
 
 ## Start a new PostgreSQL instance, with initial scripts
 
 You can pass init scripts (either shell or SQL), which will be executed the first time the container is started, to help you create the schema of your database, and populate the database.
 
-![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres4.mp4)
+![](https://github.com/containers/podman-desktop-media/raw/postgresql/videos/postgres4.gif)