Update sub_clean to also clean C tests using the .cleanfiles file
Update sub_clean to also clean C tests using the .cleanfiles file

CoryMcCartan/chapel,CoryMcCartan/chapel,chizarlicious/chapel,CoryMcCartan/chapel,chizarlicious/chapel,chizarlicious/chapel,CoryMcCartan/chapel,chizarlicious/chapel,chizarlicious/chapel,CoryMcCartan/chapel,chizarlicious/chapel,chizarlicious/chapel,CoryMcCartan/chapel,CoryMcCartan/chapel