Adding GITEA_OAUTH2_CLIENT_ENABLED to compose.yml and .env.sample

.env.sample

@@ -38,3 +38,4 @@ SECRET_SECRET_KEY_VERSION=v1 # length=64
 # GITEA_OAUTH2_USERNAME=replace-me
 # GITEA_UPDATE_AVATAR=replace-me
 # GITEA_ACCOUNT_LINKING=replace-me
+# GITEA_OAUTH2_CLIENT_ENABLED=replace-me

compose.yml

@@ -37,6 +37,7 @@ services:
       - GITEA_OAUTH2_USERNAME
       - GITEA_UPDATE_AVATAR
       - GITEA_ACCOUNT_LINKING
+      - GITEA_OAUTH2_CLIENT_ENABLED
     volumes:
       - data:/var/lib/gitea
       - config:/etc/gitea