docs: set the home directory using homedir, not home (#5101)

According to the JSON schema, the "homedir" directive should be used to
set a user's home directory. However, we use "home" in a documented
example. Supplying the example cloud-config to cloud-init schema fails
with:
  Additional properties are not allowed ('home' was unexpected),

Fixed by replacing "home" with "homedir" in the example.

LP: #2047796

doc/examples/cloud-config-user-groups.txt

@@ -142,7 +142,7 @@ users:
 #   default_user:
 #     name: Ubuntu
 #     plain_text_passwd: 'ubuntu'
-#     home: /home/ubuntu
+#     homedir: /home/ubuntu
 #     shell: /bin/bash
 #     lock_passwd: True
 #     gecos: Ubuntu

tools/.github-cla-signers

@@ -124,6 +124,7 @@ nicolasbock
 nishigori
 nkukard
 nmeyerhans
+ogayot
 olivierlemasle
 omBratteng
 onitake