What does this PR do?

Previously we use --prefix= to build unixodbc, which will search odbc.ini in $prefix/etc/odbc.ini, that is, /etc/odbc.ini.

For different linux distros and different ways of installing the msodbcsql driver, we may need to set different values ​​or variables, but here I am mainly trying to fix the default installation and use of macOS.

Checklist before merging

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  • Add your test combination to src/globals/test-extensions.php.
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