Update traffic shaping configuration for VRL expressions

Removed `pool_idle_timeout_seconds` from `traffic_shaping` and replaced it with `pool_idle_timeout` using duration format.

Author: ardatan

.changeset/shared_utilities_to_handle_vrl_expressions.md

@@ -1,9 +1,15 @@
 ---
-default: patch
+default: minor
 ---
 
-# Shared utilities to handle VRL expressions
+# Breaking
 
-#540 by @ardatan
+Removed `pool_idle_timeout_seconds` from `traffic_shaping`, instead use `pool_idle_timeout` with duration format.
 
+```diff
+traffic_shaping:
+-  pool_idle_timeout_seconds: 30
++  pool_idle_timeout: 30s
+```
 
+#540 by @ardatan