fix race in module api test for fork

in some cases we were trying to kill the fork before it got created

tests/modules/fork.c

@@ -42,7 +42,7 @@ int fork_create(RedisModuleCtx *ctx, RedisModuleString **argv, int argc)
 
     /* child */
     RedisModule_Log(ctx, "notice", "fork child started");
-    usleep(200000);
+    usleep(500000);
     RedisModule_Log(ctx, "notice", "fork child exiting");
     RedisModule_ExitFromChild(code_to_exit_with);
     /* unreachable */

tests/unit/moduleapi/fork.tcl

@@ -20,9 +20,8 @@ start_server {tags {"modules"}} {
 
     test {Module fork kill} {
         r fork.create 3
-        after 20
+        after 250
         r fork.kill
-        after 100
 
         assert {[count_log_message "fork child started"] eq "2"}
         assert {[count_log_message "Received SIGUSR1 in child"] eq "1"}