Fix lost compatibility with custom datatypes implementing .to

[awaelchli]

What does this PR do?

Fixes #2314

When I refactored the data transfer and added a model hook in #1756, I accidentally removed the ability to move non-tensor datastructures that implement .to(). This PR re-enables that via a duck typing check. For this type of data, the user is not required to override the hook, since PL can handle this out of the box now.

The test alone fails on master, confirming that the changes here fix the bug.

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[codecov]

Codecov Report

Merging #2335 into master will decrease coverage by 0%.
The diff coverage is 90%.

@@          Coverage Diff           @@
##           master   #2335   +/-   ##
======================================
- Coverage      88%     88%   -0%     
======================================
  Files          70      70           
  Lines        5512    5519    +7     
======================================
+ Hits         4851    4857    +6     
- Misses        661     662    +1     

[awaelchli]

in case someone has a suggestion for a better name, let me know :)

[Borda]

cc: @williamFalcon

[williamFalcon]

nice! great catch