fix support for project name set by COMPOSE_PROJECT_NAME env var

Signed-off-by: Nicolas De Loof <[email protected]>

cmd/compose/compose.go

@@ -175,7 +175,7 @@ func (o *ProjectOptions) toProjectName() (string, error) {
 		return o.ProjectName, nil
 	}
 
-	envProjectName := os.Getenv("ComposeProjectName")
+	envProjectName := os.Getenv(ComposeProjectName)
 	if envProjectName != "" {
 		return envProjectName, nil
 	}