Wrong font family in code blocks

[jorgepiloto]

Some code blocks in documentation render certain words without monospace font:

https://mapdl.docs.pyansys.com/version/stable/examples/gallery_examples/01-geometry/02-areas.html#area-selection

This is happening in other internal projects that do not override the CSS of this theme. Therefore, we must ensure a particular font family for code-blocks.

[jorgepiloto]

More examples in here https://fluent.docs.pyansys.com/version/stable/examples/00-fluent/lunar_lander_thermal.html#define-mean-surface-temperature-function