Update owner

Author: m-mohr

README.md

@@ -5,7 +5,7 @@
 - **Field Name Prefix:** label
 - **Scope:** Item, Collection
 - **Extension [Maturity Classification](https://github.com/radiantearth/stac-spec/tree/master/extensions/README.md#extension-maturity):** Pilot
-- **Owner**: @jisantuc
+- **Owner**: @fmigneault
 - **History**: [Prior to March 2, 2021](https://github.com/radiantearth/stac-spec/commits/v1.0.0-rc.1/extensions/label)
 
 This document explains the Label Extension to the [SpatioTemporal Asset Catalog](https://github.com/radiantearth/stac-spec) (STAC) specification.