Use consistent versions of OkHttp components. (#1256)
Use consistent versions of OkHttp components. (#1256)

We need to stick to 3.12.x versions, as newer versions don't support API
level < 21 anymore.

Closes #1253

Signed-off-by: Danny Baumann <4bceda912b479e46f041c22bcc2c9ed75fe8d5cc@web.de>
openhab/openhab.android