Bump snmalloc

Author: jvoisin

build-bench-env.sh

@@ -59,7 +59,7 @@ readonly version_sc=master   # unmaintained since 2016
 readonly version_scudo=main
 readonly version_sg=master   # ~unmaintained since 2021
 readonly version_sm=master   # ~unmaintained since 2017
-readonly version_sn=0.7.2
+readonly version_sn=0.7.3
 readonly version_tbb=v2021.9.0
 readonly version_tc=gperftools-2.16.90
 readonly version_tcg=98fd24303c7b5ef5e30da625f11fb623a5e038b6 # 2025-07-18