fix accidental save (and restore) of sigmask when interpreting try (JuliaLang#59878) (#258)

Noticed during bug hunting of
 ericphanson/LicenseCheck.jl#11 (comment)
 and may cause performance degradation for interpreter-executed try
 blocks or scope entry.

Author: kpamnany

src/interpreter.c

@@ -540,7 +540,7 @@ static jl_value_t *eval_body(jl_array_t *stmts, interpreter_state *s, size_t ip,
                 }
                 // store current top of exception stack for restore in pop_exception.
                 s->locals[jl_source_nslots(s->src) + ip] = jl_box_ulong(jl_excstack_state());
-                if (!jl_setjmp(__eh.eh_ctx, 1)) {
+                if (!jl_setjmp(__eh.eh_ctx, 0)) {
                     return eval_body(stmts, s, next_ip, toplevel);
                 }
                 else if (s->continue_at) { // means we reached a :leave expression