Isolate date -j -f ... + ... from locale.
Filed upstream as Issue #591 <https://github.com/OpenVPN/easy-rsa/issues/591>

--- easyrsa.orig	2022-05-19 01:53:50 UTC
+++ easyrsa
@@ -3829,6 +3829,8 @@ VERSION_TEXT
 NL='
 '
 
+LC_TIME=C ; export LC_TIME ; unset LC_ALL
+
 # Be secure with a restrictive umask
 [ -z "$EASYRSA_NO_UMASK" ] && umask "${EASYRSA_UMASK:-077}"