Increase PL_RESIZER_HOLD_SLACK_MARGIN

Fixes a hold violation.
diff --git a/openlane/user_project_wrapper/config.tcl b/openlane/user_project_wrapper/config.tcl
index bce43b0..3f30199 100755
--- a/openlane/user_project_wrapper/config.tcl
+++ b/openlane/user_project_wrapper/config.tcl
@@ -101,7 +101,7 @@
 
 # Placement tuning
 set ::env(PL_TARGET_DENSITY) 0.25
-set ::env(PL_RESIZER_HOLD_SLACK_MARGIN) "0.3"
+set ::env(PL_RESIZER_HOLD_SLACK_MARGIN) "0.4"
 
 set ::env(CELL_PAD) 6