Set minimum version of ruby to 1:2.5~ and add conflict with libruby2.3

debian/control

@@ -19,7 +19,7 @@ Architecture: all
 XB-Ruby-Versions: ${ruby:Versions}
 Depends: ${shlibs:Depends}, ${misc:Depends},
  gitlab-common (= ${source:Version}),
- ruby | ruby-interpreter,
+ ruby (>= 1:2.5~),
  lsb-base (>= 3.0-6),
  rake (>= 12.3.0~),
  bundler,
@@ -349,6 +349,7 @@ Depends: ${shlibs:Depends}, ${misc:Depends},
 # node-katex
 Recommends: certbot,
  gitaly (>= 1.20~)
+Conflicts: libruby2.3
 Description: git powered software platform to collaborate on code (non-omnibus)
  gitlab provides web based interface to host source code and track issues.
  It allows anyone for fork a repository and send merge requests. Code review