Replace closures with argument shuffling in second order

[gdalle]

Versions

• Bump DIT to v0.8.2 (forgot to do it in Fix ForwardDiff tags & improve StaticArrays support #571)

DI source

• In second_derivative and hvp, remove inner_derivative/gradient/pushforward and replace them with shuffled versions that use additional contexts to pass f and backend.
• Remove the private DI.nested

DI extensions

• Zygote, Tracker: Move to a closure-based handling of constants? The idea is to avoid computing pullbacks of function and backend objects if possible.
• Symbolics: Code manual second_derivative and hvp because passing constants is not supported.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.52%. Comparing base (10d63da) to head (d8beacd).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #572      +/-   ##
==========================================
+ Coverage   97.51%   97.52%   +0.01%     
==========================================
  Files         108      108              
  Lines        4903     4968      +65     
==========================================
+ Hits         4781     4845      +64     
- Misses        122      123       +1     

Flag	Coverage Δ
DI	98.68% <100.00%> (-0.01%)	⬇️
DIT	95.15% <ø> (ø)

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