Fix missing break in refer_seq (#2793)
Fix missing break in refer_seq (#2793)

Commit 9eb1687e introduced a bug in the symbol status forward
propagation where breaks are missing between the different
switch cases, causing the TRY case to fall through into the
REPEAT case.
sgebbie/ponyc,Theodus/ponyc,jemc/ponyc,dipinhora/ponyc,cquinn/ponyc,Theodus/ponyc,sgebbie/ponyc,Theodus/ponyc,kulibali/ponyc,jemc/ponyc,CausalityLtd/ponyc,sgebbie/ponyc,CausalityLtd/ponyc,dipinhora/ponyc,cquinn/ponyc,sgebbie/ponyc,kulibali/ponyc,sgebbie/ponyc,ponylang/ponyc,Theodus/ponyc,dipinhora/ponyc,CausalityLtd/ponyc,kulibali/ponyc,cquinn/ponyc,Theodus/ponyc,ponylang/ponyc,jemc/ponyc,kulibali/ponyc,cquinn/ponyc,ponylang/ponyc