dynamic_modules: prevent multiple calls to init function

[mathetake]

Commit Message: dynamic_modules: prevent multiple calls to init function
Additional Description:

Previously, the program init function was called multiple times despite the semantics of the ABI. This fixes that by utilizing RTLD_NOLOAD flag of dlopen to check a shared library is already loaded.

Risk Level: low
Testing: done
Docs Changes: n/a
Release Notes: n/a
Platform Specific Features: n/a

[repokitteh-read-only]

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🐱

Caused by: #38458 was opened by mathetake.

see: more, trace.

[mathetake]

/assign @mattklein123