Birch-Tate Conjecture

### What is the conjecture
https://en.wikipedia.org/wiki/Birch%E2%80%93Tate_conjecture#Statement

### Prerequisites needed
Requires Algebraic K-Theory Foundations.

### [AMS categories](https://github.com/google-deepmind/formal-conjectures/labels?q=ams-)

* ams-19

### Choose either option
- [ ] I plan on adding this conjecture to the repository
- [x] This issue is up for grabs: I would like to see this conjecture added by somebody else

No repository files, tests, or entry points are named. Start by reading the Birch–Tate conjecture statement on the linked Wikipedia page and reviewing the repository's Algebraic K-Theory Foundations prerequisite. Done means adding the conjecture to formal-conjectures as a formalized Lean statement.

Written by the indexing model from the issue text.