Fix link to reinit__is_reduced, sync_all_reduce

🚀 Feature

Quick issue to add the links to reinit__is_reduced and sync_all_reduce in the docs: https://pytorch.org/ignite/metrics.html#metrics-and-distributed-computations

In addition, please check if reinit__is_reduced and sync_all_reduce are used elsewhere in the docs and do not contain a link to their docs.

For Hacktoberfest contributors, feel free to ask questions for details if any and say that you would like to tackle the issue. Please, take a look at CONTRIBUTING guide.

[josselineperdomo]

Correct and

In addition, please check if reinit__is_reduced and sync_all_reduce are used elsewhere in the docs and do not contain a link to their docs.

Got it! If you agree, could you please assign me this issue? 😊

[vfdev-5]

@AnshuTrivedi idea is at first replace

In the above example, ``CustomAccuracy`` has ``reset``, ``update``, ``compute`` methods
- decorated with ``reinit__is_reduced``, ``sync_all_reduce``.
In the above example, ``CustomAccuracy`` has ``reset``, ``update``, ``compute`` methods
+ decorated with :meth:`~ignite.metrics.metric.reinit__is_reduced`, :meth:`~ignite.metrics.metric.sync_all_reduce`.

or something like that and make sure that in builded docs those words have links. See CONTRIBUTING on how to build locally the docs. Thanks !