Mqtt3 and 5 updates

What's Changed

• note about blocking callbacks in FAQ by @sbSteveK in #449
• FAQ updates by @jmklix in #450
• Android CI Testing by @sbSteveK in #433
• handle SocketOptions not being set by @jmklix in #455
• Add Mqtt5 PubSub sample to Android Testing by @sbSteveK in #451
• Doc: Fix build instruction by @alfred2g in #459
• Mqtt311 ping update, Mqtt5 extended validation relaxation by @bretambrose in #462
• AutoTag PR for v1.16.0 by @bretambrose in #464

New Contributors

• @alfred2g made their first contribution in #459

Full Changelog: v1.15.0...v1.16.0