Skip Ubuntu symbol server test

[Swatinem]

According to the FAQ at https://ubuntu.com/server/docs/service-debuginfod-faq:

Once a release goes unsupported, we [...] eventually stop serving debug symbols for its packages.

So I guess with those "stability" guarantees we either have to constantly update the testcase with up-to-date debug-ids, or we just skip it entirely :-(

#skip-changelog

[codecov]

Codecov Report

Merging #1128 (63bd614) into master (4ad4a4b) will increase coverage by 0.05%.
The diff coverage is 80.85%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1128      +/-   ##
==========================================
+ Coverage   73.89%   73.94%   +0.05%     
==========================================
  Files          86       86              
  Lines       12748    12783      +35     
==========================================
+ Hits         9420     9453      +33     
- Misses       3328     3330       +2     

[kamilogorek]

😢

[ashwoods]

For consistency, I think we should self-host whatever we want to test against.

[Swatinem]

I agree, as this evidently is a point of failure. However these tests explicitly hit these very specific external symbol servers. We also have #1004 as we hit the microsoft symbol server more than we absolutely need to. In that case we should also keep at least one test around that actually does hit it though.