Add storage migrations for Combinatorial Tokens Upgrade

[Chralt98]

What does it do?

This adds the necessary storage migrations for the changes of #1364

What important points should reviewers know?

Is there something left for follow-up PRs?

What alternative implementations were considered?

Are there relevant PRs or issues?

References

[codecov-commenter]

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Codecov Report

Attention: Patch coverage is 89.95215% with 21 lines in your changes missing coverage. Please review.

Project coverage is 93.51%. Comparing base (93f0663) to head (a932be0).

Files with missing lines	Patch %	Lines
zrml/neo-swaps/src/migration.rs	89.95%	21 Missing ⚠️

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Additional details and impacted files

@@                    Coverage Diff                     @@
##           develop-combo-futarchy    #1401      +/-   ##
==========================================================
- Coverage                   93.53%   93.51%   -0.03%     
==========================================================
  Files                         178      179       +1     
  Lines                       34547    34756     +209     
==========================================================
+ Hits                        32315    32503     +188     
- Misses                       2232     2253      +21     

Flag	Coverage Δ
tests	93.51% <89.95%> (-0.03%)	⬇️

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