Update maintainers list

Remove Gerrit reference
Change codeowners to point to group

Signed-off-by: Ry Jones <ry@linux.com>

CODEOWNERS

@@ -1,4 +1,4 @@
 # SPDX-License-Identifier: Apache-2.0
 
 # Fabric SDK Go maintainers
-*	@alikic @bstasyszyn @fqutishat @mastersingh24 @troyronda
+*	@hyperledger/fabric-sdk-go-maintainers

MAINTAINERS.md

@@ -1,17 +1,17 @@
 ## Maintainers
 
 ### Active Maintainers
-| Name | GitHub | Gerrit | email |
-|---|---|---|---|
-| Aleksandar Likic | alikic | aleksandar.likic | aleksandar.likic@securekey.com |
-| Bob Stasyszyn | bstasyszyn | bstasyszyn | bob.stasyszyn@securekey.com |
-| Firas.Qutishat | fqutishat | firas.qutishat | firas.qutishat@securekey.com |
-| Gari Singh | mastersingh24 | mastersingh24 | gari.r.singh@gmail.com |
-| Troy Ronda | troyronda | troyronda | troy@troyronda.com |
+| Name | GitHub | email |
+|---|---|---|
+| Aleksandar Likic | alikic | aleksandar.likic@securekey.com |
+| Bob Stasyszyn | bstasyszyn | bob.stasyszyn@securekey.com |
+| Firas.Qutishat | fqutishat | firas.qutishat@securekey.com |
+| Gari Singh | mastersingh24 | gari.r.singh@gmail.com |
+| Troy Ronda | troyronda | troy@troyronda.com |
 
 ### Retired Maintainers
-| Name | GitHub | Gerrit | email |
+| Name | GitHub | email |
 |---|---|---|---|
-| Jim Zhang | jimthematrix | jimthematrix | jim_the_matrix@hotmail.com |
+| Jim Zhang | jimthematrix | jim_the_matrix@hotmail.com |
 
-<a rel="license" href="http://creativecommons.org/licenses/by/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by/4.0/88x31.png" /></a><br />This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>
+<a rel="license" href="http://creativecommons.org/licenses/by/4.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by/4.0/88x31.png" /></a><br />This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by/4.0/">Creative Commons Attribution 4.0 International License</a>