[master] 246b1eb1e busyobj: Plug conceptual leak

[Dridi Boukelmoune]

commit 246b1eb1e888d6b937008da95a7776c40e1db2bc
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Tue Jul 13 07:53:44 2021 +0200

    busyobj: Plug conceptual leak
    
    It's harmless with a regular workspace, but technically we are leaving
    outstanding allocations in the workspace.

diff --git a/bin/varnishd/cache/cache_busyobj.c b/bin/varnishd/cache/cache_busyobj.c
index c6c85120e..139112854 100644
--- a/bin/varnishd/cache/cache_busyobj.c
+++ b/bin/varnishd/cache/cache_busyobj.c
@@ -181,6 +181,7 @@ VBO_ReleaseBusyObj(struct worker *wrk, struct busyobj **pbo)
 	}
 
 	VCL_Rel(&bo->vcl);
+	WS_Rollback(bo->ws, 0);
 
 	memset(&bo->retries, 0,
 	    sizeof *bo - offsetof(struct busyobj, retries));