update srouce doc pika_driver.rst the charactor then to than
update srouce doc pika_driver.rst the charactor then to than

update srouce doc pika_driver.rst the charactor
the word:more then shoud be more than

Closes-Bug: #1639995

Change-Id: I41460492c4503cf395c93b0bf643ccb98f4e12c3

ozamiatin/oslo.messaging,ozamiatin/oslo.messaging