[DRE-maint] Bug#968203: ruby2.7: ftbfs when building on buster <#<URI::HTTP http://127.0.0.1:8080>> expected but was <nil>

[Pirate Praveen]

Package: ruby2.7
Version: 2.7.1-3

This was working earlier, but now with rubygems-integration minimum 
version set to 1.17.1 one test is failing

 1) Failure:
URI::TestGeneric#test_find_proxy_no_proxy 
[/<<PKGBUILDDIR>>/test/uri/test_generic.rb:902]:
<#<URI::HTTP http://127.0.0.1:8080>> expected but was
<nil>.

Finished tests in 606.833867s, 34.5910 tests/s, 4484.9507 assertions/s.
20991 tests, 2721620 assertions, 1 failures, 0 errors, 108 skips

Initially I thought a public ipv6 address was causing the issue, but 
the same issue was therewith a scope link ipv6 address too.

Probably I will disable the test for fasttrack, but wanted to document 
it here.