Bug 21846: Regression tests for add_tag_approval

Bug 21846: Regression tests for add_tag_approval

Due to collation issues, add_tag_approval wrongly calculates
the weight for strings including extended UNICODE characters.

This patch introduces a test for this situation.

To test:
- Apply this patch on master
- Run:
  $ kshell
 k$ prove t/db_dependent/Tags.t
=> FAIL: Tests fail because all extended characters match the same

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>