Fix EVAL timeout test failed on freebsd (#10098)

* Refactor EVAL timeout test
* since the test used r config set appendonly yes which generates a rewrite, it missed it's purpose
* Fix the bug that start_server returns before redis starts ready, which affects when multiple tests share the same dir.
* Elapsed time tracking no loner needed

Co-authored-by: Oran Agra <oran@redislabs.com>

tests/integration/aof.tcl

@@ -478,26 +478,26 @@ tags {"aof external:skip"} {
     }
 
     test {EVAL timeout with slow verbatim Lua script from AOF} {
-        create_aof $aof_dirpath $aof_file {
+        start_server [list overrides [list dir $server_path appendonly yes lua-time-limit 1 aof-use-rdb-preamble no]] {  
-            append_to_aof [formatCommand select 9]
-            append_to_aof [formatCommand eval {redis.call('set',KEYS[1],'y'); for i=1,1500000 do redis.call('ping') end return 'ok'} 1 x]
-        }
-
-        start_server [list overrides [list dir $server_path appendonly no lua-time-limit 1 aof-use-rdb-preamble no]] {
             # generate a long running script that is propagated to the AOF as script
             # make sure that the script times out during loading
+            create_aof $aof_dirpath $aof_file {
+                append_to_aof [formatCommand select 9]
+                append_to_aof [formatCommand eval {redis.call('set',KEYS[1],'y'); for i=1,1500000 do redis.call('ping') end return 'ok'} 1 x]
+            }
             set rd [redis_deferring_client]
-            r config set appendonly yes
-            set start [clock clicks -milliseconds]
             $rd debug loadaof
             $rd flush
-            after 100
+            wait_for_condition 100 10 {
+                [s loading] == 1
+            } else {
+                fail "server didn't start loading"
+            }
             catch {r ping} err
             assert_match {LOADING*} $err
             $rd read
-            set elapsed [expr [clock clicks -milliseconds]-$start]
-            if {$::verbose} { puts "loading took $elapsed milliseconds" }
             $rd close
+            wait_for_log_messages 0 {"*Slow script detected*"} 0 100 100
             assert_equal [r get x] y
         }
     }

tests/support/server.tcl

@@ -505,6 +505,10 @@ proc start_server {options {code undefined}} {
         close $fd
     }
 
+    # We may have a stdout left over from the previous tests, so we need
+    # to get the current count of ready logs
+    set previous_ready_count [count_message_lines $stdout "Ready to accept"]
+
     # We need a loop here to retry with different ports.
     set server_started 0
     while {$server_started == 0} {
@@ -585,7 +589,7 @@ proc start_server {options {code undefined}} {
 
         while 1 {
             # check that the server actually started and is ready for connections
-            if {[count_message_lines $stdout "Ready to accept"] > 0} {
+            if {[count_message_lines $stdout "Ready to accept"] > $previous_ready_count} {
                 break
             }
             after 10