Remove outdated comment

lib/std/fs/file.zig

@@ -230,7 +230,6 @@ pub const File = struct {
         }
         if (self.isTty()) {
             if (self.handle == os.STDOUT_FILENO or self.handle == os.STDERR_FILENO) {
-                // Use getenvC to workaround https://github.com/ziglang/zig/issues/3511
                 if (os.getenvZ("TERM")) |term| {
                     if (std.mem.eql(u8, term, "dumb"))
                         return false;