Update Cosmos CODEOWNERS (#11500)

Co-authored-by: Steve Faulkner <[email protected]>

Author: southpolesteve

.github/CODEOWNERS

@@ -25,7 +25,7 @@
 /sdk/containerinstance/                                              @samkreter @xizhamsft
 /sdk/containerregistry/                                              @djyou
 /sdk/containerservice/                                               @samkreter @zqingqing1 @GaneshaThirumurthi
-/sdk/cosmos/                                                         @shurd
+/sdk/cosmos/                                                         @southpolesteve @zfoster
 /sdk/datafactory/                                                    @hvermis
 /sdk/datalake/                                                       @ro-joowan
 /sdk/datadatamigration/                                              @vchske