Update RFC link to point to PR

Also fix date format

Author: reedwm

rfcs/20200520-tensor-float-32.md

@@ -2,10 +2,10 @@
 
 | Status        | Proposed                                             |
 :-------------- |:---------------------------------------------------- |
-| **RFC #**     | [NNN](https://github.com/tensorflow/community/pull/NNN) (update when you have community PR #)|
+| **RFC #**     | [247](https://github.com/tensorflow/community/pull/247) |
 | **Author(s)** | Reed Wanderman-Milne ([email protected])             |
 | **Sponsor**   | Sanjoy Das ([email protected])                 |
-| **Updated**   | 2020-05/20                                           |
+| **Updated**   | 2020-05-20                                           |
 
 ## Objective