[Docs RFC] Create a doc showing how to integrate EMQX with Timescale DB

[anaghamittal]

• https://docs.google.com/document/d/1wgbGldzcEyXNLzIPuTfxkaeaJHsZCcbT3BRMGXj4Ox8/edit?tab=t.0#heading=h.gupqjbpajgbt
• https://docs.emqx.com/en/emqx/latest/data-integration/data-bridge-timescale.html