[2.4.0] Checkmk Werk 15339 created: check_sql: activate thick mode for oracle connections

[//]: # (werk v2) # check_sql: activate thick mode for oracle connections key | value ---------- | --- date | 2024-08-08T09:40:54+00:00 version | 2.4.0b1 class | fix edition | cre component | checks level | 1 compatible | yes With [Werk #16023](https://checkmk.com/werk/16023) we switched the library used to connect to oracle databases from `cx_Oracle` to `oracledb`. For `cx_Oracle` it was mandatory to install "Oracle Instant Client". The newer `oracledb` library has two modes: A stand alone thin mode and a thick mode that needs the "Oracle Instant Client". In order to fully replace `cx_Oracle`, `oracledb` needs to be in thick mode. This is something we have not considered for Werk #16023. With this Werk we now try to switch into the thick mode, and if this does not work, we use thin mode. If you execute `check_sql` with `-v` switch you will see a message if `oracledb` could not switch into thick mode. `oracledb` searches for the "Oracle Instant Client" in several standard location. `check_sql` will find the installation if the files (among other things `*.so` and `*.jar`) from the "Oracle Instant Client" files are directly in `~local/lib/` in your site.