Update variable names and defaults

Signed-off-by: Nikolaos Karaolidis <nick@karaolidis.com>

plugins/outputs/clickhouse/sample.conf

@@ -28,15 +28,15 @@
     # table_prefix = "telegraf"
 
   ## Initial metric queue size, resizes automatically if the queue becomes too large
-  # queue_size = 100000
+  # queue_initial_size = 100000
 
   ## Maximum queue size, 0 means unlimited.
   ## If the queue reaches this size, new writes will be dropped until it drains.
-  # queue_limit = 0
+  # queue_max_size = 0
 
   ## Flush interval for the metric queue
   ## The agent waits until N seconds have passed without any writes before flushing metrics to ClickHouse.
-  # queue_flush_interval = "5"
+  # queue_flush_interval = "1"
 
   ## Maximum amount of time a connection may be idle. "0s" means connections are
   ## never closed due to idle time.