Fix to determine if a decorated function has a tensor parameter

Fixes #236 .

Commits

[x] I slowed down and took a deep breadth before committing. Otherwise, I will start a pristine branch and reissue this pull request.
[x] Before committing my changes, I checked my working directory carefully. I only staged the changes I wanted and ensured it was of the utmost quality.
[x] I used git diff and git status to check my work carefully before committing.
[x] I completely understand what I am committing and why.
[x] I completely understand why things are the way they are.
[x] The change I am proposing makes complete sense to me.
[x] For the most part, the changes in this pull request correspond to the problem or task I am solving or performing. In other words, only the changes that are supposed to be there are the ones included in this pull request.

Use Ariadne's 0.9.0-SNAPSHOT, remove the TODOs of the fix in the pertinent tests and change the assert statement to the correct one.

[x] If this is a bug fix, I was able to reproduce the problem locally before I made any changes (can use git stash to temporarily reset the working directory).
[x] When I made (or put back) my changes, the problem I reproduced above was fixed.

[x] The changes I am proposing meet the expectations I have described above.
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[ ] I have commented my code, particularly in hard-to-understand areas.
[ ] I have made corresponding changes to the documentation if applicable.
[ ] I have added tests that prove my fix is effective or that my feature works if applicable.
[x] New and existing unit tests pass locally with my changes.