Update liboqs readme to point to oqs-provider instead of deprecated openssl1.1.1 fork [skip ci] #1483

Job	Run time
Check code formatting	1m 9s
Check upstream code is properly integrated	1m 7s
Check that code passes a basic build before starting heavier tests	1m 7s
linux_arm_emulated (armhf, armhf, -DOQS_ENABLE_SIG_SPHINCS=OFF -DOQS_USE_OPENSSL=OFF -DOQS_OPT_TA...	13m 20s
linux_cross_compile (windows-binaries, -DCMAKE_TOOLCHAIN_FILE=../.CMake/toolchain_windows-amd64.c...	1m 23s
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 3s
linux_intel (alpine-openssl-all, openquantumsafe/ci-alpine-amd64:latest, -DOQS_STRICT_WARNINGS=ON...	7m 25s
linux_intel (alpine-noopenssl, openquantumsafe/ci-alpine-amd64:latest, -DOQS_STRICT_WARNINGS=ON -...	5m 1s
linux_intel (focal-nistr4-openssl, openquantumsafe/ci-ubuntu-focal-x86_64:latest, -DOQS_STRICT_WA...	3m 47s
linux_intel (jammy-std-openssl3, openquantumsafe/ci-ubuntu-jammy:latest, -DOQS_STRICT_WARNINGS=ON...	3m 32s
linux_intel (address-sanitizer, openquantumsafe/ci-ubuntu-focal-x86_64:latest, -DCMAKE_C_COMPILER...	7m 48s
	52m 9s

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