[docs] Fix backticks in docs (#60474)

Summary:
There is a very common error when writing docs: One forgets to write a matching `` ` ``, and something like ``:attr:`x`` is rendered in the docs. This PR fixes most (all?) of these errors (and a few others).

I found these running ``grep -r ">[^#<][^<]*\`"`` on the `docs/build/html/generated` folder. The regex finds an HTML tag that does not start with `#` (as python comments in example code may contain backticks) and that contains a backtick in the rendered HTML.

This regex has not given any false positive in the current codebase, so I am inclined to suggest that we should add this check to the CI. Would this be possible / reasonable / easy to do malfet ?

Pull Request resolved: https://github.com/pytorch/pytorch/pull/60474

Reviewed By: mrshenli

Differential Revision: D29309633

Pulled By: albanD

fbshipit-source-id: 9621e0e9f87590cea060dd084fa367442b6bd046

torch/distributions/multinomial.py

@@ -16,11 +16,11 @@ class Multinomial(Distribution):
     called (see example below)
 
     .. note:: The `probs` argument must be non-negative, finite and have a non-zero sum,
-              and it will be normalized to sum to 1 along the last dimension. attr:`probs`
+              and it will be normalized to sum to 1 along the last dimension. :attr:`probs`
               will return this normalized value.
               The `logits` argument will be interpreted as unnormalized log probabilities
               and can therefore be any real number. It will likewise be normalized so that
-              the resulting probabilities sum to 1 along the last dimension. attr:`logits`
+              the resulting probabilities sum to 1 along the last dimension. :attr:`logits`
               will return this normalized value.
 
     -   :meth:`sample` requires a single shared `total_count` for all