Release Versioning Scheme Should Be Consistent

[ytausch]

Issue Description

I just noticed that version 1.2.0 is tagged with v1.2.0 whereas all versions before that use the x.y.z syntax without a prepended v. Probably this just was a mistake but it should be noted that changing the versioning scheme breaks automated packaging tools such as the ones interacting with the conda flask-mqtt-feedstock.

Proposed Fix

Define the tag scheme (x.y.z or vx.y.z), and use it consistently.

[Sohaib90]

Thank you for mentioning it. Will fix it