feat: more granular error messages when looking for shared objects

[govinda-kamath]

• Had run into a situation where loading libopenslide.so.1 failed because my system had an old version of libglib but the error message shown was libopenslide.so.0 not found.
• This fixes that by giving the error message for each one of the shared objects the code looks for in case it did not find any.

[openslide-bot]

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