[native] Change 'Create Community' to 'Create community'

Summary: Requested in D8379, this just changes the button copy to match the capitalization across the app

Test Plan:
Checked that button updated (screenshot below)

{F621995}

Reviewers: atul, ashoat, ginsu

Reviewed By: ashoat

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D8427

native/community-creation/community-configuration.react.js

@@ -153,7 +153,7 @@ function CommunityConfiguration(props: Props): React.Node {
         <RegistrationButtonContainer>
           <RegistrationButton
             onPress={createNewCommunity}
-            label="Create Community"
+            label="Create community"
             variant={
               createNewCommunityLoadingStatus === 'loading'
                 ? 'loading'