Changes

Update the Jenkinsfile that builds a Docker image of Silverpeas for
pro. Now, the pipeline will perform a PR by using the Github API. It
checks also if the build is just an update of an existing version of
Silverpeas

In the Silverpeas installation and upgrade test, explicits the db port for each database system under the tests

Fix Jenkinsfile for building the Docker image silverpeas/silverbuild

Update sonarcloud project id of Silverpeas-Core

Analysis code is now performed also against the stable branch of the Silverpeas projects

For both build versions and releases of Silverpeas, use now a map
between SCM branch names and versions of the Docker image to use.
Specify the branch name to Sonar when analysing the code of projects in
stable version.

Add the Sonar analysis to the Silverpeas-Looks project when building a
build version of Silverpeas

Fix bug in the Jenkinfile for releasing a minor version of Silverpeas.

Upgrade for Silverpeas 6.3-build220124

Because sks-keyservers.net is now very-dead, change with keys.openpgp.org

Update the set of data with which a user will start when testing
Silverpeas.
Now the H2 database is no more accessed directly through its database
file but through a database server that will be launched before
Silverpeas.