Add http2-client to list of topics

[joakime]

Example for Jetty team on what a in-place edit to PR looks like

[github-actions]

Diff for 1d0b788:

Printing local diff for configuration at '/home/runner/work/.eclipsefdn/.eclipsefdn/otterdog-configs/otterdog.json'

Actions are indicated with the following symbols:
+   create
!   modify
!   forced update
-   delete

Organization jetty[id=jetty]

  
!   repository[name="jetty.project"] {
!     topics                                                   = "['eclipse', 'embedded', 'fcgi', 'http', 'http-client', 'http-server', 'http2', 'http2-push', 'http3', 'https', 'jakartaee', 'java', 'jetty', 'jsp', 'osgi', 'servlet', 'ssl', 'tls', 'unix-socket', 'websockets']" -> "['eclipse', 'embedded', 'fcgi', 'http', 'http-client', 'http-server', 'http2', 'http2-client', 'http2-push', 'http3', 'https', 'jakartaee', 'java', 'jetty', 'jsp', 'osgi', 'servlet', 'ssl', 'tls', 'unix-socket', 'websockets']"
!   }
  
  Plan: 0 to add, 1 to change, 0 to delete.

Showing diff to a canonical version of the configuration at '/home/runner/work/.eclipsefdn/.eclipsefdn/otterdog-configs/otterdog.json'

Organization jetty[id=jetty]

[netomi]

A repository cannot have more than 20 topics.

need to add a validation for that.

[netomi]

going to revert that PR.

[netomi]

Created https://gitlab.eclipse.org/eclipsefdn/security/otterdog/-/issues/129 to improve the validation wrt topics.