environment: do not raise exception in detect_cuda_compiler
when the compiler is not a string.  When the compiler
is set in the build configuration (required, for example,
in a cross-build setup), the compiler setting is already
a list, which is the desired type.
@@ -1383,8 +1383,6 @@ class Environment:
for compiler in compilers:
if isinstance(compiler, str):
compiler = [compiler]
- else:
- raise EnvironmentException()
arg = '--version'
try:
p, out, err = Popen_safe(compiler + [arg])
