hpc: Fix encoding issues. Add test for and fix #17073

* Make sure files are being read/written in UTF-8. Set encoding while writing
  HTML output. Also set encoding while writing and reading .tix files although
  we don't yet have a ticket complaining that this poses problems.
* Set encoding in html header to utf8
* Upgrade to new version of 'hpc' library and reuse `readFileUtf8`
  and `writeFileUtf8` functions
* Update git submodule for `hpc`
* Bump up `hpc` executable version

Co-authored-by: Ben Gamari <ben@smart-cactus.org>
(cherry picked from commit afb23168fd28087ad0af339b559f90e3b70f2460)

1 files changed, 0 insertions, 0 deletions

diff --git a/libraries/hpc b/libraries/hpc
-Subproject 4206323affaa6cc625a6f400c3da7cdd9c30946
+Subproject f73c482db30a40cfa12074de51335b70a097493