adaftruitio_00_publish: Reduce rate to avoid data throttling

[dawoodjr]

The Arduino example, adaftruitio_00_publish, sends a message every second. Most people running that example will be using the "IO Free" plan, which only allows 30 data points per minute. And when they go to io.adafruit.com, they'll see lots of orange messages saying, "data rate limit reached. will reset in 25 seconds".

I recommend that you change the delay() at the end of the example to five seconds to avoid this problem. (Any value greater than two seconds would work, but setting it to five seconds would let someone send two feeds without hitting the throttling limit. And sending one message every five seconds is fast enough for an example.)

Thanks.

P.S., This will also solve Marc Schrieber's problem, which he posted in the Arduino forum back in August, 2017 (viewtopic.php?f=25&t=122614).