acme_dns_tiny: compute key authorization without checking token validity

Indeed, the token is created by the server

acme_dns_tiny.py

@@ -213,8 +213,7 @@ def get_crt(config, log=LOGGER):
 
         log.info("Install DNS TXT resource for domain: %s", domain)
         challenge = [c for c in authorization["challenges"] if c["type"] == "dns-01"][0]
-        token = re.sub(r"[^A-Za-z0-9_\-]", "_", challenge["token"])
-        keyauthorization = "{0}.{1}".format(token, jwk_thumbprint)
+        keyauthorization = challenge["token"] + "." + jwk_thumbprint
         keydigest64 = _base64(hashlib.sha256(keyauthorization.encode("utf8")).digest())
         dnsrr_domain = "_acme-challenge.{0}.".format(domain)
         try:  # a CNAME resource can be used for advanced TSIG configuration