test1117: reduce write delays

test1117: reduce write delays

Test1117 seems to verify that a response, incoming slowly, is read
completely before sending another request on the same connection.

The previsou write delay of 1000ms made the test last 23+ seconds.
A delay of 100ms seems to achieve the same test on modern machines, but
the overall run time is less than 3 seconds.

Closes #17530