Increase server package's coverage by adding DONTCOVER

[alessio]

Although ideally we really should find a way to test the server package
functionalities in isolation, we are in fact testing it by running the binaries.
This PR aims to increase the SDK's horrible coverage stats by largely
ignoring server.

• Linked to github-issue with discussion and accepted design OR link to spec that describes this work.
• Wrote tests
• Updated relevant documentation (docs/)
• Added a relevant changelog entry: clog add [section] [stanza] [message]
• rereviewed Files changed in the github PR explorer

---

For Admin Use:

• Added appropriate labels to PR (ex. wip, ready-for-review, docs)
• Reviewers Assigned
• Squashed all commits, uses message "Merge pull request #XYZ: [title]" (coding standards)

[codecov]

Codecov Report

Merging #4603 into master will increase coverage by 0.71%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4603      +/-   ##
==========================================
+ Coverage   52.79%   53.51%   +0.71%     
==========================================
  Files         264      261       -3     
  Lines       16468    16234     -234     
==========================================
- Hits         8695     8688       -7     
+ Misses       7126     6900     -226     
+ Partials      647      646       -1

[alexanderbez]

ACK :-/