In order to prevent regressions like #9283, lets add runtime check
against letsencrypt.org.
References: https://github.com/openwrt/openwrt/issues/9283
References: https://github.com/wolfSSL/wolfssl/issues/4879
Signed-off-by: Petr Štetiar <ynezz@true.cz>
$ uc -q -O /dev/null 'https://www.openwrt.org'
+ $ uc -q -O /dev/null 'https://letsencrypt.org'
+
$ uc -O /dev/null 'https://downloads.openwrt.org/does-not-exist' 2>&1 | grep error
HTTP error 404
$ uc -q -O /dev/null 'https://www.openwrt.org'
+ $ uc -q -O /dev/null 'https://letsencrypt.org'
+
$ uc -O /dev/null 'https://downloads.openwrt.org/does-not-exist' 2>&1 | grep error
HTTP error 404