chore(bb): fix mac build (#8522)

Author: ludamad

barretenberg/cpp/src/barretenberg/sumcheck/sumcheck.cpp

@@ -1,3 +1,7 @@
 #include "sumcheck.hpp"
 
 // Hack to make the module compile.
+
+// TODO(https://github.com/AztecProtocol/barretenberg/issues/1102): this makes the module not empty (note the comment
+// above pre-existed)
+void fixme_compile_hack() {}