Update coc and governance

CODE_OF_CONDUCT.md

 # PyTensor Code of Conduct
 
-Like the technical community as a whole, the PyTensor team and community is made
-up of a mixture of professionals and volunteers from all over the world, working
-on every aspect of the mission—including mentorship, teaching, and connecting
-people.
-
-Diversity is one of our strengths, but it can also entail communication
-issues and misunderstandings. To that end, we have a few ground rules to which we ask
-everyone to adhere.
-
-This isn’t an exhaustive list of things that you can’t do. Rather, take it in
-the spirit in which it’s intended—a guide to make it easier to enrich all of
-us and the technical communities in which we participate.
-
-This code of conduct applies to all spaces managed by the PyTensor project. This
-includes Gitter, mailing lists, the issue tracker, PyTensor events, and any other
-forums created by the project team that the community uses for communication.
-In addition, violations of this code outside these spaces may affect a person's
-ability to participate within them.
-
-If you believe someone is violating the code of conduct, we ask that you report
-it by emailing pymc.devs@gmail.com.
-
-- __Be friendly and patient.__
-
-- __Be welcoming.__ We strive to be a community that welcomes and supports people of
-  all backgrounds and identities. This includes, but is not limited to members
-  of any race, ethnicity, culture, national origin, colour, immigration status,
-  social and economic class, educational level, sex, sexual orientation, gender
-  identity and expression, age, size, family status, political belief, religion,
-  and mental and physical ability.
-
-- __Be considerate.__ Your work will be used by other people, and you in turn will
-  depend on the work of others. The decisions you make can affect users and
-  colleagues, so you should take the consequences into consideration. 
-  Remember that we're a world-wide community, so you might not be
-  communicating in someone else's primary language.
-
-- __Be respectful.__ Not all of us will agree all the time, but disagreement is no
-  excuse for poor behavior and poor manners. We might all experience some
-  frustration now and then, but we cannot allow that frustration to turn into a
-  personal attack. It’s important to remember that a community where people feel
-  uncomfortable or threatened is not a productive one. Members of the PyTensor
-  community should be respectful when dealing with other members as well as with
-  people outside the PyTensor community.
-
-- __Be careful in the words that you choose.__ We are a community of professionals,
-  and we conduct ourselves professionally. Be kind to others. Do not insult or
-  put down other participants. Harassment and other exclusionary behavior aren't
-  acceptable. This includes, but is not limited to:
-
-    - Violent threats or language directed against another person.
-    - Discriminatory jokes and language (e.g. the use of racist and sexist terms).
-    - Posting sexually explicit or violent material.
-    - Posting (or threatening to post) other people's personally identifying
-      information (e.g. "doxing").
-    - Personal insults of any sort.
-    - Unwelcome sexual attention.
-    - Advocating for, or encouraging, any of the above behavior.
-    - Repeated harassment of others. In general, if someone asks you to stop,
-      then stop.
-
-- __When we disagree, try to understand why.__ Disagreements, both social and
-  technical, happen all the time and PyTensor is no exception. It is important
-  that we resolve disagreements and differing views constructively. Remember
-  that we’re different. PyTensor benefits from its varied community and
-  people from a wide range of backgrounds. Different people have different
-  perspectives on issues. Being unable to understand why someone holds a
-  viewpoint doesn’t mean that they’re wrong. Don’t forget that it is human to
-  err and blaming each other doesn’t get us anywhere. Instead, focus on helping
-  to resolve issues and learning from mistakes.
-
-Adapted from the [Django project](https://www.djangoproject.com/conduct/).
+As a library of the PyMC project, PyTensor follows the
+[PyMC code of conduct](https://github.com/pymc-devs/pymc/blob/main/CODE_OF_CONDUCT.md).

GOVERNANCE.md

+# PyTensor Governance
+
+As a library of the PyMC project, PyTensor governance and decision making
+is described in the [main PyMC governance doc](https://github.com/pymc-devs/pymc/blob/main/GOVERNANCE.md)