MDEV-31530 Localizations for Swahili language

[lottaquestions]

• The Jira issue number for this PR is: MDEV-31530

Description

Kenyan Swahili is enabled for error messages as well as datetime.

How can this PR be tested?

The following MTR tests have been updated to test for Swahili and have all passed successfully:

• locale.test
• locales.test
• lc_time_names_basic.test
• variables.test

Basing the PR against the correct MariaDB version

• This is a new feature and the PR is based against the latest MariaDB development branch.
• This is a bug fix and the PR is based against the earliest maintained branch in which the bug can be reproduced.

PR quality check

• I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.

Copyright

All new code of the whole pull request, including one or several files that are either new files or modified ones, are contributed under the BSD-new license. I am contributing on behalf of my employer Amazon Web Services, Inc.

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[grooverdan]

Looks very good.

Reviewed against https://icu4c-demos.unicode.org/icu-bin/locexp?d_=en&_=sw_KE for the locales.

The abbreviated day names are different from the standard. Do you have reference where the "J3","J4","J5","Al","Ij","J1","J2" comes from?

Can you put the MDEV into the title of the commit message too please?

[lottaquestions]

Looks very good.

Reviewed against https://icu4c-demos.unicode.org/icu-bin/locexp?d_=en&_=sw_KE for the locales.

The abbreviated day names are different from the standard. Do you have reference where the "J3","J4","J5","Al","Ij","J1","J2" comes from?

@grooverdan I checked with other native speakers, it looks like the short names that I used are not official. I have updated the PR to use the official short names, which are basically the long names.

Can you put the MDEV into the title of the commit message too please?

MDEV added to the commit message as requested.

[grooverdan]

Thank you very much @lottaquestions