Improving the release procedure notes

Closes: opengeoweb/opengeoweb#5093 (closed)

In this MR

• Rewrite the section in the readme on creating and releasing a new version of the presets-backend
• I tried to describe the steps in a logical sense (and how I remember doing it)
• If you have some improvements/additions, please let me know!

How to test

• Check out the "Release and deploy a new version of the presets-backend" section in the readme
• Make sure the described steps make sense and there are no typos

Proposed changes to the wiki page:

• Original wiki page: https://gitlab.com/groups/opengeoweb/-/wikis/Meetings/Release-&-Deployment
• Will update the wiki after this MR has been merged
• Changed text:

---

The release is done for all shared repositories (currently this consists of the opengeoweb FE and the presets, warnings & opmet BE).

1. For the FE: follow the instruction "Release a new version and publishing to NPM"
2. For the BE: Follow the steps described at Release and deploy a new version of the presets-backend for each of the following backends:
   • Presets backend
   • Warnings backend
   • Opmet backend
   • Please note that the taf backend, cap backend, publisher backend and auth backend are also part of the shared repositories. In these repos, development is less intensive and new versions are usually created after new functionalities have been implemented (outside of the 2-week release schedule). There is no harm in checking if these repos should get a new release, but they usually(!) have a less high priority in the release process on Thursdays.
3. Make sure to ............ [page continues]