GoogleTest: Restore support for list arguments in TEST_EXECUTOR
Refactoring in !4078 (merged) accidentally parsed TEST_EXECUTOR
as a single-value argument instead of a list.
The CMAKE_CROSSCOMPILING_EMULATOR supports a semicolon-separated list (docs). In googletest this is sent to TEST_EXECUTOR which does not currently support semicolon-separated list so only the first element in the list is assigned to TEST_EXECUTOR resulting in missing arguments to the command.
Backport: release
Edited by Brad King