cmake: sca: codechecker: search for 'CodeChecker' and 'codechecker'

Let find_program in codechecker/sca.cmake search for both 'CodeChecker'
and 'codechecker'. Before this change, I wasn't able to run CodeChecker
because cmake couldn't find it. (Ubuntu 23.10, CodeChecker 6.21.0 installed
via snap)

Signed-off-by: Benedikt Streicher <streicher.b@posteo.de>