Update liboqs readme to point to oqs-provider instead of deprecated openssl1.1.1 fork [skip ci] #1484

Job	Run time
Check code formatting	1m 7s
Check upstream code is properly integrated	1m 14s
Check that code passes a basic build before starting heavier tests	1m 5s
linux_arm_emulated (armhf, armhf, -DOQS_ENABLE_SIG_SPHINCS=OFF -DOQS_USE_OPENSSL=OFF -DOQS_OPT_TA...	13m 21s
linux_cross_compile (windows-binaries, -DCMAKE_TOOLCHAIN_FILE=../.CMake/toolchain_windows-amd64.c...	1m 25s
linux_cross_compile (windows-dll, -DCMAKE_TOOLCHAIN_FILE=../.CMake/toolchain_windows-amd64.cmake ...	1m 27s
linux_intel (alpine, openquantumsafe/ci-alpine-amd64:latest, -DOQS_STRICT_WARNINGS=ON -DOQS_USE_O...	5m 9s
linux_intel (alpine-openssl-all, openquantumsafe/ci-alpine-amd64:latest, -DOQS_STRICT_WARNINGS=ON...	19m 30s
linux_intel (alpine-noopenssl, openquantumsafe/ci-alpine-amd64:latest, -DOQS_STRICT_WARNINGS=ON -...	5m 0s
linux_intel (focal-nistr4-openssl, openquantumsafe/ci-ubuntu-focal-x86_64:latest, -DOQS_STRICT_WA...	4m 7s
linux_intel (jammy-std-openssl3, openquantumsafe/ci-ubuntu-jammy:latest, -DOQS_STRICT_WARNINGS=ON...	3m 24s
linux_intel (address-sanitizer, openquantumsafe/ci-ubuntu-focal-x86_64:latest, -DCMAKE_C_COMPILER...	7m 38s
	1h 4m 27s

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