Replace sizeof() with .size()

This change replaces the usage of sizeof() with .size() to
calculate size of arrays and expressions of STL container types.
Using .size() with containers like std::vector, std::array, and
std::string improves code readability and adheres to modern C++
standards. This also helps in clang-tidy checks.

Change-Id: I1e9e6e453a3b9218682098887763a4908f186815
Signed-off-by: Pavithra Barithaya <pavithra.b@ibm.com>