Fix encoding issue exporting a project

Returns empty string on UTF8 conversion with U_STRING_NOT_TERMINATED_WARNING error

This is a workaround. Proper fix should be to return the converted string and ignore or warn about the error => https://github.com/brianmario/charlock_holmes/pull/114

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/31186

Apart from the Import/Export, we also call this function from Gitlab::Git::Blame - not sure if there're other implications there. But I assume there shouldn't.

• Changelog entry added, if necessary
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

marked the checklist item Changelog entry added, if necessary as completed

marked the checklist item Added for this feature/bug as completed

marked the checklist item Conform by the merge request performance guides as completed

marked the checklist item Conform by the style guides as completed

marked the checklist item Branch has no merge conflicts with master (if it does - rebase it please) as completed

@smcgivern small one to review... Thanks!

assigned to @smcgivern

@jameslopez LGTM, one question about the spec.

assigned to @jameslopez

assigned to @smcgivern

resolved all discussions

approved this merge request

merged

mentioned in commit 38e30516

resolved all discussions

Picked into 9-1-stable, will go into 9.1.0-rc6

mentioned in commit 843f52ea