Rename tests for nicer names in test output

With the change to test-framework, where individual tests are listed,
QCHelper tries to remove a "prop_$group_" prefix from the function
names, for shorter names. However, some test groups (LUXI) and test
functions are not uniform, leading to long names, so we should fix
them.

Signed-off-by: Iustin Pop <iustin@google.com>
Reviewed-by: Agata Murawska <agatamurawska@google.com>