Update the environment in the async worker before building the prompt

This has to be done, so that the worker has knowledge of all the
variables set that might be used by segments.

generator/default.p9k

@@ -559,10 +559,9 @@ function __p9k_prepare_prompts() {
   _P9K_TIMER_START=0x7FFFFFFF
 
   if [[ "${__P9K_DATA[async]}" == "true" ]]; then
-    # stop any running async jobs
-    async_flush_jobs "__p9k_async_worker"
-    # Update the current working directory of the async worker.
-    async_worker_eval "__p9k_async_worker" builtin cd -q $PWD
+    # Restart worker to update the environment inside the worker
+    async_stop_worker "__p9k_async_worker"
+    async_start_worker "__p9k_async_worker"
   fi
 
   __p9k_build_segment_cache "left"
@@ -579,7 +578,6 @@ p9k::set_default P9K_IGNORE_TERM_LANG false
 # @noargs
 ##
 function __p9k_ch_pwd() {
-  __p9k_prepare_prompts
   __p9k_preexec
 }