switch to sha256 for cert requests and fix for ec csr
switch to sha256 for cert requests and fix for ec csr

ato/yubico-piv-tool,akgood/yubico-piv-tool,Yubico/yubico-piv-tool,Yubico/yubico-piv-tool,hirden/yubico-piv-tool,akgood/yubico-piv-tool,Yubico/yubico-piv-tool,hirden/yubico-piv-tool,ato/yubico-piv-tool,akgood/yubico-piv-tool,akgood/yubico-piv-tool