readd version in activestorage/__init__.py for Readthedocs

[valeriupredoi]

Description

Docs build draw version from init (we may not want that, but for now it's OK)

Before you get started

• ☝ Create an issue to discuss what you are going to do

Checklist

• This pull request has a descriptive title and labels
• This pull request has a minimal description (most was discussed in the issue, but a two-liner description is still desirable)
• Unit tests have been added (if codecov test fails)
• Any changed dependencies have been added or removed correctly (if need be)
• If you are working on the documentation, please ensure the current build passes
• All tests pass

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.00%. Comparing base (e74d0ce) to head (199206a).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #282      +/-   ##
==========================================
+ Coverage   85.98%   86.00%   +0.02%     
==========================================
  Files           7        7              
  Lines         642      643       +1     
==========================================
+ Hits          552      553       +1     
  Misses         90       90              

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