SERVER-45617 - Support for Serbian language in FTS

[stef4np]

JIRA Ticket: https://jira.mongodb.org/browse/SERVER-45617

Notes:

1. codepoints_diacritic_map.cpp was changed to add removal of diacritis for Đ and đ. It had to be updated manually because it doesn't look like it is being regenerated based on the SConscript script located in the fts/unicode folder.

2. Serbian stemmer from the latest version of Snowball was adjusted for and compiled with the version of Snowball that is currently being used in MongoDB.

[kelly-cs]

Thanks for the PR! Checking in, I wanted to see if you could update this to master.

I see SERVER-45617 is still open, so I've bumped it to remind folks that this PR is available. I saw you already signed our contributor's agreement.

[stef4np]

Hello @kelly-cs,

I've updated this PR to master.

Unfortunatelly I can't build mongod from source ever since it moved on from SCons, so I can't verify if it still works like it used to.
I've tried on multiple linux instances, using both my fork and original mongodb source code and it always fails with the same error "no matching toolchains found for types @bazel_tools//tools/cpp:toolchain_type" (even though I meet all the requirements mentioned in the build doco).
Tried to make it work, but couldn't. I'll keep on trying, but just wanted to let you know that I can't verify this PR at the moment.

[kelly-cs]

Thanks @stef4np. We recently changed the build process to bazel. If it's not working for you and you suspect a bug, it would be helpful to get a SERVER ticket with your issue / what you've tried / in what environment (and I can assign it to the folks who manage our build tools).

I know there was recently an issue SERVER-98117 but that was related to SCons, not bazel.