Force push on tag creation when doing an alpha release

Scenario:

• an alpha is created on day N
• another alpha is created on day N+1
• no commits are merged on master in-between

Then the alpha creation will fail on the tag creation:

05:54:05  >>> [alpha 4.4.4.176] Creating the tag
05:54:05  fatal: tag 'alpha-4.4.4.176' already exists

We should force the tag creation + push.