Merge branch 'update-howToRelease' into 'develop'

Update HowToRelease

See merge request !519

.gitlab/issue_templates/release.md

@@ -36,7 +36,6 @@ Once all blocking issues are closed, and the previous steps are done:
     * [ ] Software Guide
     * [ ] Cookbook
     * [ ] Doxygen
-    * [ ] Application online documentation
     * [ ] WordPress page "Home" and "Download" pages
 * [ ] Upload OTB source archive to [Zenodo](https://zenodo.org/) to create a unique Digital Object Identifier (DOI)
 * [ ] Send email to mailing list to announce the release