[DRE-maint] Bug#911717: ruby2.5 FTBFS: missing Build-Depends: tzdata

[Helmut Grohne]

Source: ruby2.5
Version: 2.5.1-6
Severity: serious
Tags: ftbfs

ruby2.5 fails to build from source in unstable. The time zone tests fail
unless tzdata is installed. On the buildds, tzdata is installed, because
its Priority is required and debootstrap happens to install required
packages. tzdata is not essential nor build-essential though. You must
depend on it if you use it.

E.g.

|   1) Failure:
| TestTimeTZ#test_america_los_angeles [/<<PKGBUILDDIR>>/test/ruby/test_time_tz.rb:107]:
| TZ=America/Los_Angeles Time.local(2007, 3, 11, 2, 0, 0).
| <"2007-03-11 03:00:00 -0700"> expected but was
| <"2007-03-11 02:00:00 +0000">.

Helmut