1104 - '%s' ('%s') is not defined.
Description
    
A Function references a node which has not been defined.
    
Example
    
Config:
    Test( 'RunTest' )
{
    .TestOutput     = 'tmp/'
    .TestExecutable = 'test.exe'
}
Output:
c:\Test\fbuild.bff(1):(1) FASTBuild Error #1104 - Test() - 'TestExecutable' ('test.exe') is not defined.
Test( 'RunTest' )
^
\--here
Fix:
Executable( 'Test' )
{
    .LinkerOutput = 'test.exe'
}
Test( 'RunTest' )
{
    .TestOutput     = 'tmp/'
    .TestExecutable = 'test.exe'
}
    