📝(doc) add an example for the frontend image

I added an example in the documentation to ensure we remember to upgrade the
frontend image during the release process. This will help prevent any issues
related to outdated images when deploying new versions.

(I did this mistake while releasing)

docs/release.md

@@ -3,20 +3,28 @@
 Whenever we are cooking a new release (e.g. `4.18.1`) we should follow a standard procedure described below:
 
 1.  Create a new branch named: `release/4.18.1`.
-2.  Bump the release number for backend project, frontend projects, and Helm files:
-
-    - for backend, update the version number by hand in `pyproject.toml`,
-    - for each frontend projects (`src/frontend`, `src/mail`), run `npm version 4.18.1` in their directory. This will update both their `package.json` and `package-lock.json` for you,
-    - for Helm, update Docker image tag in files located at `src/helm/env.d` for both `preprod` and `production` environments:
-
-      ```yaml
-      image:
-        repository: lasuite/meet-backend
-        pullPolicy: Always
-        tag: "v4.18.1" # Replace with your new version number, without forgetting the "v" prefix
-      ```
-
-      The new images don't exist _yet_: they will be created automatically later in the process.
+   2.  Bump the release number for backend project, frontend projects, and Helm files:
+
+       - for backend, update the version number by hand in `pyproject.toml`,
+       - for each frontend projects (`src/frontend`, `src/mail`), run `npm version 4.18.1` in their directory. This will update both their `package.json` and `package-lock.json` for you,
+       - for Helm, update Docker image tag in files located at `src/helm/env.d` for both `preprod` and `production` environments:
+
+         ```yaml
+         image:
+           repository: lasuite/meet-backend
+           pullPolicy: Always
+           tag: "v4.18.1" # Replace with your new version number, without forgetting the "v" prefix
+
+         ...
+
+         frontend:
+           image:
+             repository: lasuite/meet-frontend
+             pullPolicy: Always
+             tag: "v4.18.1" # Replace with your new version number, without forgetting the "v" prefix
+         ```
+
+         The new images don't exist _yet_: they will be created automatically later in the process.
 
 3.  ~~Update the project's `Changelog` following the [keepachangelog](https://keepachangelog.com/en/0.3.0/) recommendations~~ _we don't keep a changelog yet for now as the project is still in its infancy. Soon™!_
 4.  Commit your changes with the following format: the 🔖 release emoji, the type of release (patch/minor/patch) and the release version: