fix: divan walltime metric #644

Job	Run time
msrv-check	43s
lint	45s
compat-integration-test-walltime (codspeed-criterion-compat)	11m 4s
compat-integration-test-instrumentation (-p codspeed)	1m 17s
compat-integration-test-instrumentation (--features async_futures -p codspeed-criterion-compat)	1m 40s
compat-integration-test-walltime (codspeed-divan-compat-examples)	3m 53s
compat-integration-test-walltime (codspeed-divan-compat)	3m 8s
compat-integration-test-instrumentation (-p codspeed-divan-compat)	1m 24s
compat-integration-test-instrumentation (-p codspeed-divan-compat-examples)	2m 13s
compat-integration-test-instrumentation (-p codspeed-bencher-compat)	1m 14s
tests	4m 39s
check	5s
	32m 5s

Provide feedback