The intention of Object/readobj-shared-object.test was to check the
general output for shared object.
I've added a case for testing dynamic objects to ELF/symbols.test.
Also we already test dynamic symbols printing in ELF/dyn-symbols.test +
I've added a case for `--dyn-syms` alias in D73164.
Hence we can remove this piece from Object/readobj-shared-object.test.
Differential revision: https://reviews.llvm.org/D73175