chore: Remove mentions of SDESolution

[DhairyaLGandhi]

Checklist

• Appropriate tests were added
• Any code changes were done in a way that does not break public API
• All documentation related to code changes were updated
• The new code follows the
  contributor guidelines, in particular the SciML Style Guide and
  COLPRAC.
• Any new documentation only uses public API

Additional context

SDESolution doesn't seem to exist anymore. The more appropriate type seems to be RODESolution. This PR removes mentions of SDESolution and replaces them with RODESolution. Further, one of the adjoints was incorrect. It was definining an adjoint over SDEProblem, but instead tries returning SDESolution in the forwards pass. Not sure how this passed tests though

Add any other context about the problem here.

[DhairyaLGandhi]

#683 (comment)

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 4 lines in your changes are missing coverage. Please review.

Project coverage is 31.74%. Comparing base (9d87ca0) to head (3e64e25).
Report is 24 commits behind head on master.

Files	Patch %	Lines
ext/SciMLBaseChainRulesCoreExt.jl	0.00%	2 Missing ⚠️
ext/SciMLBaseZygoteExt.jl	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #684      +/-   ##
==========================================
+ Coverage   31.72%   31.74%   +0.02%     
==========================================
  Files          55       55              
  Lines        4505     4505              
==========================================
+ Hits         1429     1430       +1     
+ Misses       3076     3075       -1     

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