runit(8): don't leak SIGCONT SIG_IGN into all child processes

https://inbox.vuxu.org/supervision/87tug3vzex.fsf@vuxu.org/
https://github.com/ksh93/ksh/issues/301

--- a/src/runit.c
+++ b/src/runit.c
@@ -130,7 +130,7 @@ int main (int argc, const char * const *
       sig_unblock(sig_child);
       sig_uncatch(sig_child);
       sig_unblock(sig_cont);
-      sig_ignore(sig_cont);
+      sig_uncatch(sig_cont);
       sig_unblock(sig_hangup);
       sig_unblock(sig_int);
       sig_uncatch(sig_int);