Make optional benchmark test in OpenSSL::OSSL#test_memcmp_timing #1160

Job	Run time
openssl-1.0.2u	50s
openssl-1.1.0l	53s
openssl-1.1.1w	1m 0s
openssl-3.0.14	1m 0s
openssl-3.1.6	57s
openssl-3.2.2	54s
openssl-3.3.1	1m 2s
openssl-master	3m 51s
libressl-3.1.5	57s
libressl-3.2.7	1m 3s
libressl-3.3.6	59s
libressl-3.4.3	1m 2s
libressl-3.5.3	59s
libressl-3.6.3	58s
libressl-3.7.3	53s
libressl-3.8.4	58s
libressl-3.9.2	1m 2s
openssl-3.0.14 with fips provider	43s
openssl-3.1.6 with fips provider	48s
openssl-3.2.2 with fips provider	43s
openssl-3.3.1 with fips provider	39s
openssl-master with fips provider	3m 26s
openssl-3.3.1 without legacy provider	1m 1s
ruby-versions / Generate Ruby versions	3s
ubuntu-22.04 2.7	59s
ubuntu-22.04 3.0	54s
ubuntu-22.04 3.1	1m 6s
ubuntu-22.04 3.2	57s
ubuntu-22.04 3.3	1m 0s
ubuntu-22.04 head	59s
ubuntu-22.04 truffleruby	1m 31s
ubuntu-22.04 truffleruby-head	1m 41s
ubuntu-20.04 2.7	57s
ubuntu-20.04 3.0	53s
ubuntu-20.04 3.1	59s
ubuntu-20.04 3.2	56s
ubuntu-20.04 3.3	55s
ubuntu-20.04 head	58s
ubuntu-20.04 truffleruby	1m 32s
ubuntu-20.04 truffleruby-head	1m 35s
macos-latest 2.7	50s
macos-latest 3.0	40s
macos-latest 3.1	40s
macos-latest 3.2	42s
macos-latest 3.3	55s
macos-latest head	42s
macos-latest truffleruby	1m 12s
macos-latest truffleruby-head	1m 0s
windows-latest 2.7	5m 38s
windows-latest 3.0	4m 15s
windows-latest 3.1	4m 34s
windows-latest 3.2	4m 15s
windows-latest 3.3	4m 26s
windows-latest head	3m 47s
windows-latest ucrt	3m 58s
windows-latest mswin	2m 46s
	1h 24m 53s

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