Minimize unsafe C functions usage - replace strcat() and strcpy() - continued

[robinnewhouse]

Description

567b681 introduced safe_strcpy() to minimize the use of C with potentially unsafe memory overflow with strcpy() whose use is discouraged. Replace instances of strcpy() with safe_strcpy() where possible, limited here to files in the sql/ directory.

How can this PR be tested?

All passing MTR tests still pass. Tested manually and in CI.

Basing the PR against the correct MariaDB version

• [x] 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

• [x] I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.

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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[robinnewhouse]

Marked as WIP. Investigating failing MTR tests.

[ottok]

@arun-esh Would you like to review this? It is somewhat similar to your #2573.

[robinnewhouse]

Removed changes that were the cause of failing tests. Could this be reviewed? cc @arun-esh

[robinnewhouse]

Is this ok to push to 10.4 or would you like me to rebase to 10.5?

[vuvova]

I'd suggest 10.5, just to be on the safe side. We're doing the very last 10.4 within a couple of weeks.

[robinnewhouse]

@vuvova Rebased to 10.5 @cvicentiu Updated indentation.