Reduce OpenSSL::Buffering#do_write overhead #1290

Job	Run time
openssl-1.0.2u	5m 48s
openssl-1.1.0l	5m 46s
openssl-1.1.1w	5m 50s
openssl-3.0.15	5m 54s
openssl-3.1.7	5m 47s
openssl-3.2.3	5m 50s
openssl-3.3.2	5m 48s
openssl-3.4.0	5m 50s
openssl-master	8m 36s
libressl-3.1.5	5m 52s
libressl-3.2.7	5m 44s
libressl-3.3.6	5m 51s
libressl-3.4.3	5m 57s
libressl-3.5.3	5m 45s
libressl-3.6.3	5m 46s
libressl-3.7.3	5m 44s
libressl-3.8.4	5m 45s
libressl-3.9.2	5m 44s
libressl-4.0.0	5m 43s
openssl-3.0.15 with fips provider	5m 48s
openssl-3.1.7 with fips provider	5m 46s
openssl-3.2.3 with fips provider	5m 54s
openssl-3.3.2 with fips provider	5m 49s
openssl-3.4.0 with fips provider	5m 55s
openssl-master with fips provider	8m 39s
openssl-3.4.0 without legacy provider	5m 55s
ruby-versions / Generate Ruby versions	1s
ubuntu-22.04 2.7	5m 55s
ubuntu-22.04 3.0	5m 45s
ubuntu-22.04 3.1	5m 50s
ubuntu-22.04 3.2	5m 45s
ubuntu-22.04 3.3	5m 47s
ubuntu-22.04 head	1m 4s
ubuntu-22.04 truffleruby	6m 5s
ubuntu-22.04 truffleruby-head	6m 7s
ubuntu-20.04 2.7	5m 54s
ubuntu-20.04 3.0	5m 47s
ubuntu-20.04 3.1	5m 52s
ubuntu-20.04 3.2	5m 51s
ubuntu-20.04 3.3	5m 51s
ubuntu-20.04 head	1m 0s
ubuntu-20.04 truffleruby	5m 59s
ubuntu-20.04 truffleruby-head	6m 11s
macos-latest 2.7	5m 54s
macos-latest 3.0	5m 41s
macos-latest 3.1	5m 38s
macos-latest 3.2	5m 35s
macos-latest 3.3	5m 35s
macos-latest head	39s
macos-latest truffleruby	5m 46s
macos-latest truffleruby-head	5m 46s
windows-latest 2.7	10m 38s
windows-latest 3.0	9m 4s
windows-latest 3.1	8m 51s
windows-latest 3.2	9m 3s
windows-latest 3.3	9m 14s
windows-latest head	4m 2s
windows-latest ucrt	4m 0s
windows-latest mswin	3m 8s
	5h 40m 4s

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