test/reline/test_terminfo.rb: skip when setupterm fails

http://rubyci.s3.amazonaws.com/solaris11-gcc/ruby-master/log/20210806T000008Z.fail.html.gz
```
  1) Error:
Reline::Terminfo::Test#test_tigetstr:
Reline::Terminfo::TerminfoError: The terminfo database could not be found.
    /export/home/chkbuild/chkbuild-gcc/tmp/build/20210806T000008Z/ruby/lib/reline/terminfo.rb:84:in `setupterm'
    /export/home/chkbuild/chkbuild-gcc/tmp/build/20210806T000008Z/ruby/test/reline/test_terminfo.rb:6:in `setup'
```

test/reline/test_terminfo.rb

@@ -4,6 +4,8 @@ require "reline"
 class Reline::Terminfo::Test < Reline::TestCase
   def setup
     Reline::Terminfo.setupterm(0, 2)
+  rescue Reline::Terminfo::TerminfoError
+    skip "Reline::Terminfo does not work"
   end
 
   def test_tigetstr