Eliminate the built-in SNTP support (fixes #4207): (#4628)

cfg/rippled-example.cfg

@@ -463,19 +463,6 @@
 #
 #
 #
-# [sntp_servers]
-#
-#   IP address or domain of NTP servers to use for time synchronization.
-#
-#   These NTP servers are suitable for rippled servers located in the United
-#   States:
-#      time.windows.com
-#      time.apple.com
-#      time.nist.gov
-#      pool.ntp.org
-#
-#
-#
 # [max_transactions]
 #
 #   Configure the maximum number of transactions to have in the job queue
@@ -1716,12 +1703,6 @@ advisory_delete=0
 [debug_logfile]
 /var/log/rippled/debug.log
 
-[sntp_servers]
-time.windows.com
-time.apple.com
-time.nist.gov
-pool.ntp.org
-
 # To use the XRP test network
 # (see https://xrpl.org/connect-your-rippled-to-the-xrp-test-net.html),
 # use the following [ips] section:

cfg/rippled-reporting.cfg

@@ -450,19 +450,6 @@
 #
 #
 #
-# [sntp_servers]
-#
-#   IP address or domain of NTP servers to use for time synchronization.
-#
-#   These NTP servers are suitable for rippled servers located in the United
-#   States:
-#      time.windows.com
-#      time.apple.com
-#      time.nist.gov
-#      pool.ntp.org
-#
-#
-#
 # [max_transactions]
 #
 #   Configure the maximum number of transactions to have in the job queue
@@ -1662,12 +1649,6 @@ advisory_delete=0
 [debug_logfile]
 /var/log/rippled-reporting/debug.log
 
-[sntp_servers]
-time.windows.com
-time.apple.com
-time.nist.gov
-pool.ntp.org
-
 # To use the XRP test network
 # (see https://xrpl.org/connect-your-rippled-to-the-xrp-test-net.html),
 # use the following [ips] section: